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[Qemu-devel] [PATCH] Major overhaul of block-vvfat
|
From: |
Johannes Schindelin |
|
Subject: |
[Qemu-devel] [PATCH] Major overhaul of block-vvfat |
|
Date: |
Sat, 10 Dec 2005 16:09:58 -0000 |
Thanks to malc, I started working on this again. It should now work reliably
in read-only mode. The read/write support is somewhat beta. That is, it works
for my setup, but it might well break under obscure conditions.
What has changed? A lot. For example, it is now possible to emulate a floppy:
-fda fat:floppy:my_directory/
Note that while a floppy is eject'able, the maximum size the guest OSes
accepted in my tests was 2.88MB. Not very much.
To add write/support, do
-fda fat:floppy:rw:my_directory/
To have a sane write support, I had to include the bdrv_make_empty() patch
I sent to the list a few weeks ago, since it was not applied...
What you *never* should do:
- use non-ASCII filenames.
- use "-snapshot" together with ":rw:".
- expect it to work when loadvm'ing.
What's next?
- add bootsector support
- fix bugs which were sent to me by helpful people
- add a timeout so that a commit is only tried after some time
has passed since the last sector was written
- maybe support FAT32 (I am not yet convinced that this is needed)
- maybe create block-visofs, so that huge files can be mapped into
the guest system, and be updated via "eject" in the monitor
- world domination!
Signed-off-by: Johannes Schindelin <address@hidden>
---
block-qcow.c | 58 +
block-vvfat.c | 2930 +++++++++++++++++++++++++++++++++++++++------------------
block.c | 16
block_int.h | 3
4 files changed, 2050 insertions(+), 957 deletions(-)
diff --git a/block-qcow.c b/block-qcow.c
index ca05be8..34026a4 100644
--- a/block-qcow.c
+++ b/block-qcow.c
@@ -552,25 +552,28 @@ static int qcow_create(const char *filen
header_size = sizeof(header);
backing_filename_len = 0;
if (backing_file) {
- const char *p;
- /* XXX: this is a hack: we do not attempt to check for URL
- like syntax */
- p = strchr(backing_file, ':');
- if (p && (p - backing_file) >= 2) {
- /* URL like but exclude "c:" like filenames */
- pstrcpy(backing_filename, sizeof(backing_filename),
- backing_file);
- } else {
- realpath(backing_file, backing_filename);
- if (stat(backing_filename, &st) != 0) {
- return -1;
- }
- }
+ if (strcmp(backing_file, "fat:")) {
+ const char *p;
+ /* XXX: this is a hack: we do not attempt to check for URL
+ like syntax */
+ p = strchr(backing_file, ':');
+ if (p && (p - backing_file) >= 2) {
+ /* URL like but exclude "c:" like filenames */
+ pstrcpy(backing_filename, sizeof(backing_filename),
+ backing_file);
+ } else {
+ realpath(backing_file, backing_filename);
+ if (stat(backing_filename, &st) != 0) {
+ return -1;
+ }
+ }
+ header.backing_file_offset = cpu_to_be64(header_size);
+ backing_filename_len = strlen(backing_filename);
+ header.backing_file_size = cpu_to_be32(backing_filename_len);
+ header_size += backing_filename_len;
+ } else
+ backing_file = NULL;
header.mtime = cpu_to_be32(st.st_mtime);
- header.backing_file_offset = cpu_to_be64(header_size);
- backing_filename_len = strlen(backing_filename);
- header.backing_file_size = cpu_to_be32(backing_filename_len);
- header_size += backing_filename_len;
header.cluster_bits = 9; /* 512 byte cluster to avoid copying
unmodifyed sectors */
header.l2_bits = 12; /* 32 KB L2 tables */
@@ -603,6 +606,24 @@ static int qcow_create(const char *filen
return 0;
}
+int qcow_make_empty(BlockDriverState *bs)
+{
+ BDRVQcowState *s = bs->opaque;
+ uint32_t l1_length = s->l1_size * sizeof(uint64_t);
+
+ memset(s->l1_table, 0, l1_length);
+ lseek(s->fd, s->l1_table_offset, SEEK_SET);
+ if (write(s->fd, s->l1_table, l1_length) < 0)
+ return -1;
+ ftruncate(s->fd, s->l1_table_offset + l1_length);
+
+ memset(s->l2_cache, 0, s->l2_size * L2_CACHE_SIZE * sizeof(uint64_t));
+ memset(s->l2_cache_offsets, 0, L2_CACHE_SIZE * sizeof(uint64_t));
+ memset(s->l2_cache_counts, 0, L2_CACHE_SIZE * sizeof(uint32_t));
+
+ return 0;
+}
+
int qcow_get_cluster_size(BlockDriverState *bs)
{
BDRVQcowState *s = bs->opaque;
@@ -683,6 +704,7 @@ BlockDriver bdrv_qcow = {
qcow_create,
qcow_is_allocated,
qcow_set_key,
+ qcow_make_empty
};
diff --git a/block-vvfat.c b/block-vvfat.c
index 3409f88..720bbda 100644
--- a/block-vvfat.c
+++ b/block-vvfat.c
@@ -1,7 +1,8 @@
+/* vim:set shiftwidth=4 ts=8: */
/*
* QEMU Block driver for virtual VFAT (shadows a local directory)
*
- * Copyright (c) 2004 Johannes E. Schindelin
+ * Copyright (c) 2004,2005 Johannes E. Schindelin
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
deal
@@ -27,19 +28,47 @@
#include "vl.h"
#include "block_int.h"
-// TODO: new file
-// TODO: delete file
-// TODO: make root directory larger
-// TODO: make directory clusters connected, so they are reserved anyway... add
a member which tells how many clusters are reserved after a directory
-// TODO: introduce another member in mapping_t which says where the directory
resides in s->directory (for mkdir and rmdir)
-// in _read and _write, before treating direntries or file contents,
get_mapping to know what it is.
-// TODO: mkdir
-// TODO: rmdir
+#ifndef S_IWGRP
+#define S_IWGRP 0
+#endif
+#ifndef S_IWOTH
+#define S_IWOTH 0
+#endif
+
+/* TODO: add ":bootsector=blabla.img:" */
+/* LATER TODO: add automatic boot sector generation from
+ BOOTEASY.ASM and Ranish Partition Manager
+ Note that DOS assumes the system files to be the first files in the
+ file system (test if the boot sector still relies on that fact)! */
+/* MAYBE TODO: write block-visofs.c */
+/* TODO: call try_commit() only after a timeout */
+
+/* #define DEBUG */
+
+#ifdef DEBUG
+
+#define DLOG(a) a
+
+#undef stderr
+#define stderr STDERR
+FILE* stderr = NULL;
-// TODO: when commit_data'ing a direntry and is_consistent, commit_remove
-// TODO: reset MODE_MODIFIED when commit_remove'ing
+static void checkpoint();
-#define DEBUG
+#ifdef __MINGW32__
+void nonono(const char* file, int line, const char* msg) {
+ fprintf(stderr, "Nonono! %s:%d %s\n", file, line, msg);
+ exit(-5);
+}
+#undef assert
+#define assert(a) if (!(a)) nonono(__FILE__, __LINE__, #a)
+#endif
+
+#else
+
+#define DLOG(a)
+
+#endif
/* dynamic array functions */
typedef struct array_t {
@@ -62,23 +91,37 @@ static inline void array_free(array_t* a
array->size=array->next=0;
}
-/* make sure that memory is reserved at pointer[index*item_size] */
+/* does not automatically grow */
static inline void* array_get(array_t* array,unsigned int index) {
- if((index+1)*array->item_size>array->size) {
- int new_size=(index+32)*array->item_size;
- array->pointer=realloc(array->pointer,new_size);
- if(!array->pointer)
- return 0;
- array->size=new_size;
- array->next=index+1;
+ assert(index >= 0);
+ assert(index < array->next);
+ return array->pointer + index * array->item_size;
+}
+
+static inline int array_ensure_allocated(array_t* array, int index)
+{
+ if((index + 1) * array->item_size > array->size) {
+ int new_size = (index + 32) * array->item_size;
+ array->pointer = realloc(array->pointer, new_size);
+ if (!array->pointer)
+ return -1;
+ array->size = new_size;
+ array->next = index + 1;
}
- return array->pointer+index*array->item_size;
+
+ return 0;
}
static inline void* array_get_next(array_t* array) {
- unsigned int next=array->next;
- void* result=array_get(array,next);
- array->next=next+1;
+ unsigned int next = array->next;
+ void* result;
+
+ if (array_ensure_allocated(array, next) < 0)
+ return NULL;
+
+ array->next = next + 1;
+ result = array_get(array, next);
+
return result;
}
@@ -132,14 +175,32 @@ static inline int array_roll(array_t* ar
return 0;
}
-int array_remove(array_t* array,int index)
+inline int array_remove_slice(array_t* array,int index, int count)
{
- if(array_roll(array,array->next-1,index,1))
+ assert(index >=0);
+ assert(count > 0);
+ assert(index + count <= array->next);
+ if(array_roll(array,array->next-1,index,count))
return -1;
- array->next--;
+ array->next -= count;
return 0;
}
+int array_remove(array_t* array,int index)
+{
+ return array_remove_slice(array, index, 1);
+}
+
+/* return the index for a given member */
+int array_index(array_t* array, void* pointer)
+{
+ size_t offset = (char*)pointer - array->pointer;
+ assert(offset >= 0);
+ assert((offset % array->item_size) == 0);
+ assert(offset/array->item_size < array->next);
+ return offset/array->item_size;
+}
+
/* These structures are used to fake a disk and the VFAT filesystem.
* For this reason we need to use __attribute__((packed)). */
@@ -151,7 +212,7 @@ typedef struct bootsector_t {
uint16_t reserved_sectors;
uint8_t number_of_fats;
uint16_t root_entries;
- uint16_t zero;
+ uint16_t total_sectors16;
uint8_t media_type;
uint16_t sectors_per_fat;
uint16_t sectors_per_track;
@@ -186,7 +247,7 @@ typedef struct partition_t {
uint8_t start_head;
uint8_t start_sector;
uint8_t start_cylinder;
- uint8_t fs_type; /* 0x6 = FAT16, 0xb = FAT32 */
+ uint8_t fs_type; /* 0x1 = FAT12, 0x6 = FAT16, 0xb = FAT32 */
uint8_t end_head;
uint8_t end_sector;
uint8_t end_cylinder;
@@ -218,32 +279,44 @@ typedef struct direntry_t {
/* this structure are used to transparently access the files */
typedef struct mapping_t {
- /* begin is the first cluster, end is the last+1,
- * offset is the offset in the file in clusters of this slice */
- off_t begin,end,offset;
- char* filename;
-
+ /* begin is the first cluster, end is the last+1 */
+ uint32_t begin,end;
/* as s->directory is growable, no pointer may be used here */
unsigned int dir_index;
- enum {
MODE_NORMAL,MODE_UNDEFINED,MODE_MODIFIED,MODE_DELETED,MODE_DIRECTORY } mode;
+ /* the clusters of a file may be in any order; this points to the first */
+ int first_mapping_index;
+ union {
+ /* offset is
+ * - the offset in the file (in clusters) for a file, or
+ * - the next cluster of the directory for a directory, and
+ * - the address of the buffer for a faked entry
+ */
+ struct {
+ uint32_t offset;
+ } file;
+ struct {
+ int parent_mapping_index;
+ int first_dir_index;
+ } dir;
+ } info;
+ /* path contains the full path, i.e. it always starts with s->path */
+ char* path;
+
+ enum { MODE_UNDEFINED = 0, MODE_NORMAL = 1, MODE_MODIFIED = 2,
+ MODE_DIRECTORY = 4, MODE_FAKED = 8,
+ MODE_DELETED = 16, MODE_RENAMED = 32 } mode;
+ int read_only;
} mapping_t;
-/* this structure is used to hold sectors which need to be written, but it's
- * not known yet where to write them. */
-
-typedef struct commit_t {
- uint32_t cluster_num;
- uint8_t* buf;
-} commit_t;
-
-/* write support exists for fat, direntry and file contents */
-typedef enum {
- WRITE_UNDEFINED,WRITE_FAT,WRITE_DIRENTRY,WRITE_DATA
-} write_action_t;
+#ifdef DEBUG
+static void print_direntry(const struct direntry_t*);
+static void print_mapping(const struct mapping_t* mapping);
+#endif
/* here begins the real VVFAT driver */
typedef struct BDRVVVFATState {
+ BlockDriverState* bs; /* pointer to parent */
unsigned int first_sectors_number; /* 1 for a single partition, 0x40 for a
disk with partition table */
unsigned char first_sectors[0x40*0x200];
@@ -254,31 +327,33 @@ typedef struct BDRVVVFATState {
unsigned int sectors_per_cluster;
unsigned int sectors_per_fat;
unsigned int sectors_of_root_directory;
- unsigned int sectors_for_directory;
+ uint32_t last_cluster_of_root_directory;
unsigned int faked_sectors; /* how many sectors are faked before file data
*/
uint32_t sector_count; /* total number of sectors of the partition */
uint32_t cluster_count; /* total number of clusters of this partition */
- unsigned int first_file_mapping; /* index of the first mapping which is
not a directory, but a file */
uint32_t max_fat_value;
int current_fd;
- char current_fd_is_writable; /* =0 if read only, !=0 if read/writable */
mapping_t* current_mapping;
- unsigned char* cluster;
+ unsigned char* cluster; /* points to current cluster */
+ unsigned char* cluster_buffer; /* points to a buffer to hold temp data */
unsigned int current_cluster;
/* write support */
- array_t commit;
- /* for each file, the file contents, the direntry, and the fat entries are
- * written, but not necessarily in that order */
- write_action_t action[3];
+ BlockDriverState* write_target;
+ char* qcow_filename;
+ BlockDriverState* qcow;
+ void* fat2;
+ char* used_clusters;
+ array_t commits;
+ const char* path;
+ int downcase_short_names;
} BDRVVVFATState;
static int vvfat_probe(const uint8_t *buf, int buf_size, const char *filename)
{
- if (strstart(filename, "fat:", NULL) ||
- strstart(filename, "fatrw:", NULL))
+ if (strstart(filename, "fat:", NULL))
return 100;
return 0;
}
@@ -295,16 +370,19 @@ static void init_mbr(BDRVVVFATState* s)
partition->start_head=1;
partition->start_sector=1;
partition->start_cylinder=0;
- partition->fs_type=(s->fat_type==16?0x6:0xb); /* FAT16/FAT32 */
- partition->end_head=0xf;
+ /* FAT12/FAT16/FAT32 */
+ partition->fs_type=(s->fat_type==12?0x1:s->fat_type==16?0x6:0xb);
+ partition->end_head=s->bs->heads-1;
partition->end_sector=0xff; /* end sector & upper 2 bits of cylinder */;
partition->end_cylinder=0xff; /* lower 8 bits of end cylinder */;
- partition->start_sector_long=cpu_to_le32(0x3f);
+ partition->start_sector_long=cpu_to_le32(s->bs->secs);
partition->end_sector_long=cpu_to_le32(s->sector_count);
real_mbr->magic[0]=0x55; real_mbr->magic[1]=0xaa;
}
+/* direntry functions */
+
/* dest is assumed to hold 258 bytes, and pads with 0xffff up to next multiple
of 26 */
static inline int short2long_name(unsigned char* dest,const char* src)
{
@@ -344,9 +422,62 @@ static inline direntry_t* create_long_fi
return array_get(&(s->directory),s->directory.next-number_of_entries);
}
+static char is_free(const direntry_t* direntry)
+{
+ /* return direntry->name[0]==0 ; */
+ return direntry->attributes == 0 || direntry->name[0]==0xe5;
+}
+
+static char is_volume_label(const direntry_t* direntry)
+{
+ return direntry->attributes == 0x28;
+}
+
+static char is_long_name(const direntry_t* direntry)
+{
+ return direntry->attributes == 0xf;
+}
+
+static char is_short_name(const direntry_t* direntry)
+{
+ return !is_volume_label(direntry) && !is_long_name(direntry)
+ && !is_free(direntry);
+}
+
+static char is_directory(const direntry_t* direntry)
+{
+ return direntry->attributes & 0x10 && direntry->name[0] != 0xe5;
+}
+
+static inline char is_dot(const direntry_t* direntry)
+{
+ return is_short_name(direntry) && direntry->name[0] == '.';
+}
+
+static char is_file(const direntry_t* direntry)
+{
+ return is_short_name(direntry) && !is_directory(direntry);
+}
+
+static inline uint32_t begin_of_direntry(const direntry_t* direntry)
+{
+ return le16_to_cpu(direntry->begin)|(le16_to_cpu(direntry->begin_hi)<<16);
+}
+
+static inline uint32_t filesize_of_direntry(const direntry_t* direntry)
+{
+ return le32_to_cpu(direntry->size);
+}
+
+static void set_begin_of_direntry(direntry_t* direntry, uint32_t begin)
+{
+ direntry->begin = cpu_to_le16(begin & 0xffff);
+ direntry->begin_hi = cpu_to_le16((begin >> 16) & 0xffff);
+}
+
/* fat functions */
-static inline uint8_t fat_chksum(direntry_t* entry)
+static inline uint8_t fat_chksum(const direntry_t* entry)
{
uint8_t chksum=0;
int i;
@@ -375,29 +506,39 @@ static uint16_t fat_datetime(time_t time
static inline void fat_set(BDRVVVFATState* s,unsigned int cluster,uint32_t
value)
{
- if(s->fat_type==12) {
- assert(0); /* TODO */
+ if(s->fat_type==32) {
+ uint32_t* entry=array_get(&(s->fat),cluster);
+ *entry=cpu_to_le32(value);
} else if(s->fat_type==16) {
uint16_t* entry=array_get(&(s->fat),cluster);
*entry=cpu_to_le16(value&0xffff);
} else {
- uint32_t* entry=array_get(&(s->fat),cluster);
- *entry=cpu_to_le32(value);
+ int offset = (cluster*3/2);
+ unsigned char* p = array_get(&(s->fat), offset);
+ switch (cluster&1) {
+ case 0:
+ p[0] = value&0xff;
+ p[1] = (p[1]&0xf0) | ((value>>8)&0xf);
+ break;
+ case 1:
+ p[0] = (p[0]&0xf) | ((value&0xf)<<4);
+ p[1] = (value>>4);
+ break;
+ }
}
}
static inline uint32_t fat_get(BDRVVVFATState* s,unsigned int cluster)
{
- //fprintf(stderr,"want to get fat for cluster %d\n",cluster);
- if(s->fat_type==12) {
- const uint8_t* x=s->fat.pointer+cluster*3/2;
- return ((x[0]|(x[1]<<8))>>(cluster&1?4:0))&0x0fff;
+ if(s->fat_type==32) {
+ uint32_t* entry=array_get(&(s->fat),cluster);
+ return le32_to_cpu(*entry);
} else if(s->fat_type==16) {
uint16_t* entry=array_get(&(s->fat),cluster);
return le16_to_cpu(*entry);
} else {
- uint32_t* entry=array_get(&(s->fat),cluster);
- return le32_to_cpu(*entry);
+ const uint8_t* x=s->fat.pointer+cluster*3/2;
+ return ((x[0]|(x[1]<<8))>>(cluster&1?4:0))&0x0fff;
}
}
@@ -410,69 +551,32 @@ static inline int fat_eof(BDRVVVFATState
static inline void init_fat(BDRVVVFATState* s)
{
- int i;
-
- array_init(&(s->fat),(s->fat_type==32?4:2));
- array_get(&(s->fat),s->sectors_per_fat*0x200/s->fat.item_size-1);
+ if (s->fat_type == 12) {
+ array_init(&(s->fat),1);
+ array_ensure_allocated(&(s->fat),
+ s->sectors_per_fat * 0x200 * 3 / 2 - 1);
+ } else {
+ array_init(&(s->fat),(s->fat_type==32?4:2));
+ array_ensure_allocated(&(s->fat),
+ s->sectors_per_fat * 0x200 / s->fat.item_size - 1);
+ }
memset(s->fat.pointer,0,s->fat.size);
- fat_set(s,0,0x7ffffff8);
- for(i=1;i<s->sectors_for_directory/s->sectors_per_cluster-1;i++)
- fat_set(s,i,i+1);
- fat_set(s,i,0x7fffffff);
-
switch(s->fat_type) {
case 12: s->max_fat_value=0xfff; break;
case 16: s->max_fat_value=0xffff; break;
- case 32: s->max_fat_value=0xfffffff; break;
+ case 32: s->max_fat_value=0x0fffffff; break;
default: s->max_fat_value=0; /* error... */
}
}
-static inline int long2unix_name(unsigned char* dest,int dest_size,direntry_t*
direntry_short) {
- int i=-1,j;
- int chksum=fat_chksum(direntry_short);
- while(1) {
- char* buf=(char*)(direntry_short+i);
- if((buf[0]&0x3f)!=-i || direntry_short[i].reserved[1]!=chksum ||
- direntry_short[i].attributes!=0xf) {
- if(i<-1)
- return -3;
- /* take short name */
- for(j=7;j>0 && direntry_short->name[j]==' ';j--);
- if(j+1>dest_size)
- return -1;
- strncpy(dest,direntry_short->name,j+1);
- dest+=j+1; dest_size-=j+1;
- for(j=2;j>=0 && direntry_short->extension[j]==' ';j--);
- if(j>=0) {
- if(j+2>dest_size)
- return -1;
- dest[0]='.';
- strncpy(dest+1,direntry_short->extension,j+1);
- }
- return 0;
- }
- for(j=0;j<13;j++) {
- dest_size--;
- if(dest_size<0)
- return -2;
- dest[0]=buf[2*j+((j<5)?1:(j<11)?4:6)];
- if(dest[0]==0 && (buf[0]&0x40)!=0)
- return 0;
- dest++;
- }
- /* last entry, but no trailing \0? */
- if(buf[0]&0x40)
- return -3;
- i--;
- }
-}
-
-static inline direntry_t* create_short_filename(BDRVVVFATState* s,unsigned int
directory_start,const char* filename,int is_dot)
+/* TODO: in create_short_filename, 0xe5->0x05 is not yet handled! */
+/* TODO: in parse_short_filename, 0x05->0xe5 is not yet handled! */
+static inline direntry_t* create_short_and_long_name(BDRVVVFATState* s,
+ unsigned int directory_start, const char* filename, int is_dot)
{
- int i,long_index=s->directory.next;
+ int i,j,long_index=s->directory.next;
direntry_t* entry=0;
direntry_t* entry_long=0;
@@ -483,26 +587,28 @@ static inline direntry_t* create_short_f
return entry;
}
- for(i=1;i<8 && filename[i] && filename[i]!='.';i++);
-
entry_long=create_long_filename(s,filename);
-
+
+ i = strlen(filename);
+ for(j = i - 1; j>0 && filename[j]!='.';j--);
+ if (j > 0)
+ i = (j > 8 ? 8 : j);
+ else if (i > 8)
+ i = 8;
+
entry=array_get_next(&(s->directory));
memset(entry->name,0x20,11);
strncpy(entry->name,filename,i);
- if(filename[i]) {
- int len=strlen(filename);
- for(i=len;i>0 && filename[i-1]!='.';i--);
- if(i>0)
- memcpy(entry->extension,filename+i,(len-i>3?3:len-i));
- }
+ if(j > 0)
+ for (i = 0; i < 3 && filename[j+1+i]; i++)
+ entry->extension[i] = filename[j+1+i];
/* upcase & remove unwanted characters */
for(i=10;i>=0;i--) {
- if(i==10 || i==7) for(;i>1 && entry->name[i]==' ';i--);
+ if(i==10 || i==7) for(;i>0 && entry->name[i]==' ';i--);
if(entry->name[i]<=' ' || entry->name[i]>0x7f
- || strchr("*?<>|\":/\\[];,+='",entry->name[i]))
+ || strchr(".*?<>|\":/\\[];,+='",entry->name[i]))
entry->name[i]='_';
else if(entry->name[i]>='a' && entry->name[i]<='z')
entry->name[i]+='A'-'a';
@@ -514,7 +620,7 @@ static inline direntry_t* create_short_f
int j;
for(;entry1<entry;entry1++)
- if(!(entry1->attributes&0xf) &&
!memcmp(entry1->name,entry->name,11))
+ if(!is_long_name(entry1) && !memcmp(entry1->name,entry->name,11))
break; /* found dupe */
if(entry1==entry) /* no dupe found */
break;
@@ -543,8 +649,7 @@ static inline direntry_t* create_short_f
/* calculate anew, because realloc could have taken place */
entry_long=array_get(&(s->directory),long_index);
- while(entry_long<entry
- && entry_long->attributes==0xf) {
+ while(entry_long<entry && is_long_name(entry_long)) {
entry_long->reserved[1]=chksum;
entry_long++;
}
@@ -553,33 +658,48 @@ static inline direntry_t* create_short_f
return entry;
}
-static int read_directory(BDRVVVFATState* s,const char* dirname,
- int first_cluster_of_parent)
+/*
+ * Read a directory. (the index of the corresponding mapping must be passed).
+ */
+static int read_directory(BDRVVVFATState* s, int mapping_index)
{
+ mapping_t* mapping = array_get(&(s->mapping), mapping_index);
+ direntry_t* direntry;
+ const char* dirname = mapping->path;
+ int first_cluster = mapping->begin;
+ int parent_index = mapping->info.dir.parent_mapping_index;
+ mapping_t* parent_mapping = (mapping_t*)
+ (parent_index >= 0 ? array_get(&(s->mapping), parent_index) : 0);
+ int first_cluster_of_parent = parent_mapping ? parent_mapping->begin : -1;
DIR* dir=opendir(dirname);
struct dirent* entry;
- struct stat st;
- unsigned int start_of_directory=s->directory.next;
- /* mappings before first_file_mapping are directories */
- unsigned int first_directory_mapping=s->first_file_mapping;
- unsigned int
first_cluster=(start_of_directory/0x10/s->sectors_per_cluster);
int i;
- if(!dir)
+ assert(mapping->mode & MODE_DIRECTORY);
+
+ if(!dir) {
+ mapping->end = mapping->begin;
return -1;
-
+ }
+
+ i = mapping->info.dir.first_dir_index =
+ first_cluster == 0 ? 0 : s->directory.next;
+
+ /* actually read the directory, and allocate the mappings */
while((entry=readdir(dir))) {
unsigned int length=strlen(dirname)+2+strlen(entry->d_name);
char* buffer;
direntry_t* direntry;
+ struct stat st;
int is_dot=!strcmp(entry->d_name,".");
int is_dotdot=!strcmp(entry->d_name,"..");
- if(start_of_directory==1 && (is_dotdot || is_dot))
+ if(first_cluster == 0 && (is_dotdot || is_dot))
continue;
buffer=(char*)malloc(length);
+ assert(buffer);
snprintf(buffer,length,"%s/%s",dirname,entry->d_name);
if(stat(buffer,&st)<0) {
@@ -588,8 +708,8 @@ static int read_directory(BDRVVVFATState
}
/* create directory entry for this file */
- //fprintf(stderr,"create direntry at %d (cluster %d) for
%s\n",s->directory.next,s->directory.next/0x10/s->sectors_per_cluster,entry->d_name);
-
direntry=create_short_filename(s,start_of_directory,entry->d_name,is_dot||is_dotdot);
+ direntry=create_short_and_long_name(s, i, entry->d_name,
+ is_dot || is_dotdot);
direntry->attributes=(S_ISDIR(st.st_mode)?0x10:0x20);
direntry->reserved[0]=direntry->reserved[1]=0;
direntry->ctime=fat_datetime(st.st_ctime,1);
@@ -599,25 +719,40 @@ static int read_directory(BDRVVVFATState
direntry->mtime=fat_datetime(st.st_mtime,1);
direntry->mdate=fat_datetime(st.st_mtime,0);
if(is_dotdot)
- direntry->begin=cpu_to_le16(first_cluster_of_parent);
+ set_begin_of_direntry(direntry, first_cluster_of_parent);
else if(is_dot)
- direntry->begin=cpu_to_le16(first_cluster);
+ set_begin_of_direntry(direntry, first_cluster);
else
- direntry->begin=cpu_to_le16(0); /* do that later */
- direntry->size=cpu_to_le32(st.st_size);
+ direntry->begin=0; /* do that later */
+ if (st.st_size > 0x7fffffff) {
+ fprintf(stderr, "File %s is larger than 2GB\n", buffer);
+ free(buffer);
+ return -2;
+ }
+ direntry->size=cpu_to_le32(S_ISDIR(st.st_mode)?0:st.st_size);
/* create mapping for this file */
- if(!is_dot && !is_dotdot) {
- if(S_ISDIR(st.st_mode))
-
s->current_mapping=(mapping_t*)array_insert(&(s->mapping),s->first_file_mapping++,1);
- else
- s->current_mapping=(mapping_t*)array_get_next(&(s->mapping));
+ if(!is_dot && !is_dotdot && (S_ISDIR(st.st_mode) || st.st_size)) {
+ s->current_mapping=(mapping_t*)array_get_next(&(s->mapping));
s->current_mapping->begin=0;
s->current_mapping->end=st.st_size;
- s->current_mapping->offset=0;
- s->current_mapping->filename=buffer;
+ /*
+ * we get the direntry of the most recent direntry, which
+ * contains the short name and all the relevant information.
+ */
s->current_mapping->dir_index=s->directory.next-1;
-
s->current_mapping->mode=(S_ISDIR(st.st_mode)?MODE_DIRECTORY:MODE_UNDEFINED);
+ s->current_mapping->first_mapping_index = -1;
+ if (S_ISDIR(st.st_mode)) {
+ s->current_mapping->mode = MODE_DIRECTORY;
+ s->current_mapping->info.dir.parent_mapping_index =
+ mapping_index;
+ } else {
+ s->current_mapping->mode = MODE_UNDEFINED;
+ s->current_mapping->info.file.offset = 0;
+ }
+ s->current_mapping->path=buffer;
+ s->current_mapping->read_only =
+ (st.st_mode & (S_IWUSR | S_IWGRP | S_IWOTH)) == 0;
}
}
closedir(dir);
@@ -628,89 +763,78 @@ static int read_directory(BDRVVVFATState
memset(direntry,0,sizeof(direntry_t));
}
- /* reserve next cluster also (for new files) */
- for(i=0;i<0x10*s->sectors_per_cluster;i++) {
- direntry_t* direntry=array_get_next(&(s->directory));
- memset(direntry,0,sizeof(direntry_t));
+/* TODO: if there are more entries, bootsector has to be adjusted! */
+#define ROOT_ENTRIES (0x02 * 0x10 * s->sectors_per_cluster)
+ if (mapping_index == 0 && s->directory.next < ROOT_ENTRIES) {
+ /* root directory */
+ int cur = s->directory.next;
+ array_ensure_allocated(&(s->directory), ROOT_ENTRIES - 1);
+ memset(array_get(&(s->directory), cur), 0,
+ (ROOT_ENTRIES - cur) * sizeof(direntry_t));
}
+
+ /* reget the mapping, since s->mapping was possibly realloc()ed */
+ mapping = (mapping_t*)array_get(&(s->mapping), mapping_index);
+ first_cluster += (s->directory.next - mapping->info.dir.first_dir_index)
+ * 0x20 / s->cluster_size;
+ mapping->end = first_cluster;
- /* was it the first directory? */
- if(start_of_directory==1) {
- mapping_t* mapping=array_insert(&(s->mapping),0,1);
- mapping->filename=strdup(dirname);
- mapping->mode=MODE_DIRECTORY;
- mapping->begin=0;
- mapping->end=1;
- mapping->offset=0;
- mapping->dir_index=0xffffffff;
- s->sectors_of_root_directory=s->directory.next/0x10;
- }
+ direntry = (direntry_t*)array_get(&(s->directory), mapping->dir_index);
+ set_begin_of_direntry(direntry, mapping->begin);
+
+ return 0;
+}
- /* recurse directories */
- {
- int i;
+static inline uint32_t sector2cluster(BDRVVVFATState* s,off_t sector_num)
+{
+ return (sector_num-s->faked_sectors)/s->sectors_per_cluster;
+}
- //fprintf(stderr,"iterating subdirectories of %s (first cluster %d): %d
to %d\n",dirname,first_cluster,first_directory_mapping,last_directory_mapping);
- for(i=first_directory_mapping;i<s->first_file_mapping;i++) {
- mapping_t* mapping=array_get(&(s->mapping),i);
- direntry_t* direntry=array_get(&(s->directory),mapping->dir_index);
- /* the directory to be read can add more subdirectories */
- int last_dir_mapping=s->first_file_mapping;
-
- assert(mapping->mode==MODE_DIRECTORY);
- /* first, tell the mapping where the directory will start */
- mapping->begin=s->directory.next/0x10/s->sectors_per_cluster;
- if(i>0) {
- mapping[-1].end=mapping->begin;
- assert(mapping[-1].begin<mapping->begin);
- }
- /* then tell the direntry */
- direntry->begin=cpu_to_le16(mapping->begin);
- //fprintf(stderr,"read directory %s (begin
%d)\n",mapping->filename,(int)mapping->begin);
- /* then read it */
- if(read_directory(s,mapping->filename,first_cluster))
- return -1;
+static inline off_t cluster2sector(BDRVVVFATState* s, uint32_t cluster_num)
+{
+ return s->faked_sectors + s->sectors_per_cluster * cluster_num;
+}
- if(last_dir_mapping!=s->first_file_mapping) {
- int diff=s->first_file_mapping-last_dir_mapping;
- assert(diff>0);
-
- if(last_dir_mapping!=i+1) {
- int count=last_dir_mapping-i-1;
- int to=s->first_file_mapping-count;
-
- assert(count>0);
- assert(to>i+1);
- array_roll(&(s->mapping),to,i+1,count);
- /* could have changed due to realloc */
- mapping=array_get(&(s->mapping),i);
- mapping->end=mapping[1].begin;
- }
- i+=diff;
- }
- }
- }
+static inline uint32_t sector_offset_in_cluster(BDRVVVFATState* s,off_t
sector_num)
+{
+ return
(sector_num-s->first_sectors_number-2*s->sectors_per_fat)%s->sectors_per_cluster;
+}
- return 0;
+#ifdef DBG
+static direntry_t* get_direntry_for_mapping(BDRVVVFATState* s,mapping_t*
mapping)
+{
+ if(mapping->mode==MODE_UNDEFINED)
+ return 0;
+ return
(direntry_t*)(s->directory.pointer+sizeof(direntry_t)*mapping->dir_index);
}
+#endif
-static int init_directory(BDRVVVFATState* s,const char* dirname)
+static int init_directories(BDRVVVFATState* s,
+ const char* dirname)
{
- bootsector_t*
bootsector=(bootsector_t*)&(s->first_sectors[(s->first_sectors_number-1)*0x200]);
+ bootsector_t* bootsector;
+ mapping_t* mapping;
unsigned int i;
unsigned int cluster;
memset(&(s->first_sectors[0]),0,0x40*0x200);
- /* TODO: if FAT32, this is probably wrong */
- s->sectors_per_fat=0xec;
- s->sectors_per_cluster=0x10;
s->cluster_size=s->sectors_per_cluster*0x200;
- s->cluster=malloc(s->cluster_size);
+ s->cluster_buffer=malloc(s->cluster_size);
+ assert(s->cluster_buffer);
+
+ /*
+ * The formula: sc = spf+1+spf*spc*(512*8/fat_type),
+ * where sc is sector_count,
+ * spf is sectors_per_fat,
+ * spc is sectors_per_clusters, and
+ * fat_type = 12, 16 or 32.
+ */
+ i = 1+s->sectors_per_cluster*0x200*8/s->fat_type;
+ s->sectors_per_fat=(s->sector_count+i)/i; /* round up */
array_init(&(s->mapping),sizeof(mapping_t));
array_init(&(s->directory),sizeof(direntry_t));
- array_init(&(s->commit),sizeof(commit_t));
/* add volume label */
{
@@ -719,69 +843,86 @@ static int init_directory(BDRVVVFATState
snprintf(entry->name,11,"QEMU VVFAT");
}
- if(read_directory(s,dirname,0))
- return -1;
-
- /* make sure that the number of directory entries is multiple of
0x200/0x20 (to fit the last sector exactly) */
- s->sectors_for_directory=s->directory.next/0x10;
-
-
s->faked_sectors=s->first_sectors_number+s->sectors_per_fat*2+s->sectors_for_directory;
- s->cluster_count=(s->sector_count-s->faked_sectors)/s->sectors_per_cluster;
-
/* Now build FAT, and write back information into directory */
init_fat(s);
- cluster=s->sectors_for_directory/s->sectors_per_cluster;
- assert(s->sectors_for_directory%s->sectors_per_cluster==0);
-
- /* set the end of the last read directory */
- if(s->first_file_mapping>0) {
- mapping_t* mapping=array_get(&(s->mapping),s->first_file_mapping-1);
- mapping->end=cluster;
- }
+ s->faked_sectors=s->first_sectors_number+s->sectors_per_fat*2;
+ s->cluster_count=sector2cluster(s, s->sector_count);
- for(i=1;i<s->mapping.next;i++) {
- mapping_t* mapping=array_get(&(s->mapping),i);
- direntry_t* direntry=array_get(&(s->directory),mapping->dir_index);
- if(mapping->mode==MODE_DIRECTORY) {
- /* directory */
- int i;
-#ifdef DEBUG
- fprintf(stderr,"assert: %s %d <
%d\n",mapping->filename,(int)mapping->begin,(int)mapping->end);
-#endif
- assert(mapping->begin<mapping->end);
- for(i=mapping->begin;i<mapping->end-1;i++)
- fat_set(s,i,i+1);
- fat_set(s,i,0x7fffffff);
- } else {
- /* as the space is virtual, we can be sloppy about it */
- unsigned int end_cluster=cluster+mapping->end/s->cluster_size;
+ mapping = array_get_next(&(s->mapping));
+ mapping->begin = 0;
+ mapping->dir_index = 0;
+ mapping->info.dir.parent_mapping_index = -1;
+ mapping->first_mapping_index = -1;
+ mapping->path = strdup(dirname);
+ i = strlen(mapping->path);
+ if (i > 0 && mapping->path[i - 1] == '/')
+ mapping->path[i - 1] = '\0';
+ mapping->mode = MODE_DIRECTORY;
+ mapping->read_only = 0;
+ s->path = mapping->path;
- if(end_cluster>=s->cluster_count) {
- fprintf(stderr,"Directory does not fit in FAT%d\n",s->fat_type);
+ for (i = 0, cluster = 0; i < s->mapping.next; i++) {
+ int j;
+ /* MS-DOS expects the FAT to be 0 for the root directory
+ * (except for the media byte). */
+ /* LATER TODO: still true for FAT32? */
+ int fix_fat = (i != 0);
+ mapping = array_get(&(s->mapping), i);
+
+ if (mapping->mode & MODE_DIRECTORY) {
+ mapping->begin = cluster;
+ if(read_directory(s, i)) {
+ fprintf(stderr, "Could not read directory %s\n",
+ mapping->path);
return -1;
}
- mapping->begin=cluster;
+ mapping = array_get(&(s->mapping), i);
+ } else {
+ assert(mapping->mode == MODE_UNDEFINED);
mapping->mode=MODE_NORMAL;
- mapping->offset=0;
- direntry->size=cpu_to_le32(mapping->end);
- if(direntry->size==0) {
- direntry->begin=0;
- mapping->end=cluster;
- continue;
+ mapping->begin = cluster;
+ if (mapping->end > 0) {
+ direntry_t* direntry = array_get(&(s->directory),
+ mapping->dir_index);
+
+ mapping->end = cluster + 1 + (mapping->end-1)/s->cluster_size;
+ set_begin_of_direntry(direntry, mapping->begin);
+ } else {
+ mapping->end = cluster + 1;
+ fix_fat = 0;
}
+ }
+
+ assert(mapping->begin < mapping->end);
+
+ /* fix fat for entry */
+ if (fix_fat) {
+ for(j = mapping->begin; j < mapping->end - 1; j++)
+ fat_set(s, j, j+1);
+ fat_set(s, mapping->end - 1, s->max_fat_value);
+ }
- direntry->begin=cpu_to_le16(cluster);
- mapping->end=end_cluster+1;
- for(;cluster<end_cluster;cluster++)
- fat_set(s,cluster,cluster+1);
- fat_set(s,cluster,0x7fffffff);
- cluster++;
+ /* next free cluster */
+ cluster = mapping->end;
+
+ if(cluster > s->cluster_count) {
+ fprintf(stderr,"Directory does not fit in FAT%d\n",s->fat_type);
+ return -1;
}
}
- s->current_mapping=0;
+ mapping = array_get(&(s->mapping), 0);
+ s->sectors_of_root_directory = mapping->end * s->sectors_per_cluster;
+ s->last_cluster_of_root_directory = mapping->end;
+
+ /* the FAT signature */
+ fat_set(s,0,s->max_fat_value);
+ fat_set(s,1,s->max_fat_value);
+
+ s->current_mapping = NULL;
+
bootsector=(bootsector_t*)(s->first_sectors+(s->first_sectors_number-1)*0x200);
bootsector->jump[0]=0xeb;
bootsector->jump[1]=0x3e;
bootsector->jump[2]=0x90;
@@ -791,17 +932,17 @@ static int init_directory(BDRVVVFATState
bootsector->reserved_sectors=cpu_to_le16(1);
bootsector->number_of_fats=0x2; /* number of FATs */
bootsector->root_entries=cpu_to_le16(s->sectors_of_root_directory*0x10);
- bootsector->zero=0;
- bootsector->media_type=(s->first_sectors_number==1?0xf0:0xf8); /* media
descriptor */
+
bootsector->total_sectors16=s->sector_count>0xffff?0:cpu_to_le16(s->sector_count);
+
bootsector->media_type=(s->fat_type!=12?0xf8:s->sector_count==5760?0xf9:0xf8);
/* media descriptor */
+ s->fat.pointer[0] = bootsector->media_type;
bootsector->sectors_per_fat=cpu_to_le16(s->sectors_per_fat);
- bootsector->sectors_per_track=cpu_to_le16(0x3f);
- bootsector->number_of_heads=cpu_to_le16(0x10);
+ bootsector->sectors_per_track=cpu_to_le16(s->bs->secs);
+ bootsector->number_of_heads=cpu_to_le16(s->bs->heads);
bootsector->hidden_sectors=cpu_to_le32(s->first_sectors_number==1?0:0x3f);
- /* TODO: if FAT32, adjust */
- bootsector->total_sectors=cpu_to_le32(s->sector_count);
+
bootsector->total_sectors=cpu_to_le32(s->sector_count>0xffff?s->sector_count:0);
- /* TODO: if FAT32, this is wrong */
- bootsector->u.fat16.drive_number=0x80; /* assume this is hda (TODO) */
+ /* LATER TODO: if FAT32, this is wrong */
+ bootsector->u.fat16.drive_number=s->fat_type==12?0:0x80; /* assume this is
hda (TODO) */
bootsector->u.fat16.current_head=0;
bootsector->u.fat16.signature=0x29;
bootsector->u.fat16.id=cpu_to_le32(0xfabe1afd);
@@ -813,52 +954,106 @@ static int init_directory(BDRVVVFATState
return 0;
}
+static BDRVVVFATState *vvv = NULL;
+
+static int enable_write_target(BDRVVVFATState *s);
+static int is_consistent(BDRVVVFATState *s);
+
static int vvfat_open(BlockDriverState *bs, const char* dirname)
{
BDRVVVFATState *s = bs->opaque;
+ int floppy = 0;
int i;
- /* TODO: automatically determine which FAT type */
+ vvv = s;
+
+DLOG(if (stderr == NULL) {
+ stderr = fopen("vvfat.log", "a");
+ setbuf(stderr, NULL);
+})
+
+ s->bs = bs;
+
s->fat_type=16;
+ /* LATER TODO: if FAT32, adjust */
s->sector_count=0xec04f;
+ s->sectors_per_cluster=0x10;
+ /* LATER TODO: this could be wrong for FAT32 */
+ bs->cyls=1023; bs->heads=15; bs->secs=63;
s->current_cluster=0xffffffff;
- s->first_file_mapping=0;
- /* TODO: if simulating a floppy, this is 1, because there is no partition
table */
s->first_sectors_number=0x40;
+ /* read only is the default for safety */
+ bs->read_only = 1;
+ s->qcow = s->write_target = NULL;
+ s->qcow_filename = NULL;
+ s->fat2 = NULL;
+ s->downcase_short_names = 1;
- if (strstart(dirname, "fat:", &dirname)) {
- /* read only is the default for safety */
- bs->read_only = 1;
- } else if (strstart(dirname, "fatrw:", &dirname)) {
- /* development only for now */
- bs->read_only = 0;
- } else {
- return -1;
+ if (!strstart(dirname, "fat:", NULL))
+ return -1;
+
+ if (strstr(dirname, ":rw:")) {
+ if (enable_write_target(s))
+ return -1;
+ bs->read_only = 0;
}
- if(init_directory(s,dirname))
+
+ if (strstr(dirname, ":floppy:")) {
+ floppy = 1;
+ s->fat_type = 12;
+ s->first_sectors_number = 1;
+ s->sectors_per_cluster=2;
+ bs->cyls = 80; bs->heads = 2; bs->secs = 36;
+ }
+
+ if (strstr(dirname, ":32:")) {
+ fprintf(stderr, "Big fat greek warning: FAT32 has not been tested. You
are welcome to do so!\n");
+ s->fat_type = 32;
+ } else if (strstr(dirname, ":16:")) {
+ s->fat_type = 16;
+ } else if (strstr(dirname, ":12:")) {
+ s->fat_type = 12;
+ s->sector_count=2880;
+ }
+
+ i = strrchr(dirname, ':') - dirname;
+ assert(i >= 3);
+ if (dirname[i-2] == ':' && isalpha(dirname[i-1]))
+ /* workaround for DOS drive names */
+ dirname += i-1;
+ else
+ dirname += i+1;
+
+ bs->total_sectors=bs->cyls*bs->heads*bs->secs;
+ if (s->sector_count > bs->total_sectors)
+ s->sector_count = bs->total_sectors;
+ if(init_directories(s, dirname))
return -1;
if(s->first_sectors_number==0x40)
init_mbr(s);
- /* TODO: this could be wrong for FAT32 */
- bs->cyls=1023; bs->heads=15; bs->secs=63;
- bs->total_sectors=bs->cyls*bs->heads*bs->secs;
+ /* for some reason or other, MS-DOS does not like to know about CHS... */
+ if (floppy)
+ bs->heads = bs->cyls = bs->secs = 0;
+
+ assert(is_consistent(s));
- /* write support */
- for(i=0;i<3;i++)
- s->action[i]=WRITE_UNDEFINED;
return 0;
}
static inline void vvfat_close_current_file(BDRVVVFATState *s)
{
if(s->current_mapping) {
- s->current_mapping = 0;
- close(s->current_fd);
+ s->current_mapping = NULL;
+ if (s->current_fd) {
+ close(s->current_fd);
+ s->current_fd = 0;
+ }
}
+ s->current_cluster = -1;
}
/* mappings between index1 and index2-1 are supposed to be ordered
@@ -867,23 +1062,27 @@ static inline void vvfat_close_current_f
static inline int find_mapping_for_cluster_aux(BDRVVVFATState* s,int
cluster_num,int index1,int index2)
{
int index3=index1+1;
- //fprintf(stderr,"find_aux: cluster_num=%d,
index1=%d,index2=%d\n",cluster_num,index1,index2);
while(1) {
mapping_t* mapping;
index3=(index1+index2)/2;
mapping=array_get(&(s->mapping),index3);
- //fprintf(stderr,"index3: %d = (%d+%d)/2, end:
%d\n",index3,index1,index2,(int)mapping->end);
- if(mapping->end>cluster_num) {
+ assert(mapping->begin < mapping->end);
+ if(mapping->begin>=cluster_num) {
assert(index2!=index3 || index2==0);
if(index2==index3)
- return index2;
+ return index1;
index2=index3;
} else {
if(index1==index3)
- return index2;
+ return mapping->end<=cluster_num ? index2 : index1;
index1=index3;
}
assert(index1<=index2);
+ DLOG(mapping=array_get(&(s->mapping),index1);
+ assert(mapping->begin<=cluster_num);
+ assert(index2 >= s->mapping.next ||
+ ((mapping = array_get(&(s->mapping),index2)) &&
+ mapping->end>cluster_num)));
}
}
@@ -896,24 +1095,41 @@ static inline mapping_t* find_mapping_fo
mapping=array_get(&(s->mapping),index);
if(mapping->begin>cluster_num)
return 0;
+ assert(mapping->begin<=cluster_num && mapping->end>cluster_num);
return mapping;
}
-static int open_file(BDRVVVFATState* s,mapping_t* mapping,int flags)
+/*
+ * This function simply compares path == mapping->path. Since the mappings
+ * are sorted by cluster, this is expensive: O(n).
+ */
+static inline mapping_t* find_mapping_for_path(BDRVVVFATState* s,
+ const char* path)
+{
+ int i;
+
+ for (i = 0; i < s->mapping.next; i++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+ if (mapping->first_mapping_index < 0 &&
+ !strcmp(path, mapping->path))
+ return mapping;
+ }
+
+ return NULL;
+}
+
+static int open_file(BDRVVVFATState* s,mapping_t* mapping)
{
if(!mapping)
return -1;
- assert(flags==O_RDONLY || flags==O_RDWR);
if(!s->current_mapping ||
- strcmp(s->current_mapping->filename,mapping->filename) ||
- (flags==O_RDWR && !s->current_fd_is_writable)) {
+ strcmp(s->current_mapping->path,mapping->path)) {
/* open file */
- int fd = open(mapping->filename, flags | O_BINARY | O_LARGEFILE);
+ int fd = open(mapping->path, O_RDONLY | O_BINARY | O_LARGEFILE);
if(fd<0)
return -1;
vvfat_close_current_file(s);
s->current_fd = fd;
- s->current_fd_is_writable = (flags==O_RDWR?-1:0);
s->current_mapping = mapping;
}
return 0;
@@ -924,18 +1140,39 @@ static inline int read_cluster(BDRVVVFAT
if(s->current_cluster != cluster_num) {
int result=0;
off_t offset;
+ assert(!s->current_mapping || s->current_fd ||
(s->current_mapping->mode & MODE_DIRECTORY));
if(!s->current_mapping
|| s->current_mapping->begin>cluster_num
|| s->current_mapping->end<=cluster_num) {
/* binary search of mappings for file */
mapping_t* mapping=find_mapping_for_cluster(s,cluster_num);
- if(open_file(s,mapping,O_RDONLY))
+
+ assert(!mapping || (cluster_num>=mapping->begin &&
cluster_num<mapping->end));
+
+ if (mapping && mapping->mode & MODE_DIRECTORY) {
+ vvfat_close_current_file(s);
+ s->current_mapping = mapping;
+read_cluster_directory:
+ offset =
s->cluster_size*(cluster_num-s->current_mapping->begin);
+ s->cluster = s->directory.pointer+offset
+ + 0x20*s->current_mapping->info.dir.first_dir_index;
+ assert(((s->cluster-(unsigned
char*)s->directory.pointer)%s->cluster_size)==0);
+ assert((char*)s->cluster+s->cluster_size <=
s->directory.pointer+s->directory.next*s->directory.item_size);
+ s->current_cluster = cluster_num;
+ return 0;
+ }
+
+ if(open_file(s,mapping))
return -2;
- }
+ } else if (s->current_mapping->mode & MODE_DIRECTORY)
+ goto read_cluster_directory;
-
offset=s->cluster_size*(cluster_num-s->current_mapping->begin+s->current_mapping->offset);
+ assert(s->current_fd);
+
+
offset=s->cluster_size*(cluster_num-s->current_mapping->begin)+s->current_mapping->info.file.offset;
if(lseek(s->current_fd, offset, SEEK_SET)!=offset)
return -3;
+ s->cluster=s->cluster_buffer;
result=read(s->current_fd,s->cluster,s->cluster_size);
if(result<0) {
s->current_cluster = -1;
@@ -946,774 +1183,1565 @@ static inline int read_cluster(BDRVVVFAT
return 0;
}
-static int vvfat_read(BlockDriverState *bs, int64_t sector_num,
- uint8_t *buf, int nb_sectors)
+#ifdef DEBUG
+static void hexdump(const void* address, uint32_t len)
{
- BDRVVVFATState *s = bs->opaque;
- int i;
+ const unsigned char* p = address;
+ int i, j;
- // fprintf(stderr,"vvfat_read: sector
%d+%d\n",(int)sector_num,nb_sectors);
-
- for(i=0;i<nb_sectors;i++,sector_num++) {
- if(sector_num<s->faked_sectors) {
- if(sector_num<s->first_sectors_number)
-
memcpy(buf+i*0x200,&(s->first_sectors[sector_num*0x200]),0x200);
- else if(sector_num-s->first_sectors_number<s->sectors_per_fat)
-
memcpy(buf+i*0x200,&(s->fat.pointer[(sector_num-s->first_sectors_number)*0x200]),0x200);
- else
if(sector_num-s->first_sectors_number-s->sectors_per_fat<s->sectors_per_fat)
-
memcpy(buf+i*0x200,&(s->fat.pointer[(sector_num-s->first_sectors_number-s->sectors_per_fat)*0x200]),0x200);
- else
if(sector_num-s->first_sectors_number-s->sectors_per_fat*2<s->sectors_for_directory)
-
memcpy(buf+i*0x200,&(s->directory.pointer[(sector_num-s->first_sectors_number-s->sectors_per_fat*2)*0x200]),0x200);
- } else {
- uint32_t
sector=sector_num-s->first_sectors_number-s->sectors_per_fat*2,
- sector_offset_in_cluster=(sector%s->sectors_per_cluster),
- cluster_num=sector/s->sectors_per_cluster;
- if(read_cluster(s, cluster_num) != 0) {
- //fprintf(stderr,"failed to read cluster
%d\n",(int)cluster_num);
- // TODO: strict: return -1;
- memset(buf+i*0x200,0,0x200);
- continue;
- }
-
memcpy(buf+i*0x200,s->cluster+sector_offset_in_cluster*0x200,0x200);
- }
+ for (i = 0; i < len; i += 16) {
+ for (j = 0; j < 16 && i + j < len; j++)
+ fprintf(stderr, "%02x ", p[i + j]);
+ for (; j < 16; j++)
+ fprintf(stderr, " ");
+ fprintf(stderr, " ");
+ for (j = 0; j < 16 && i + j < len; j++)
+ fprintf(stderr, "%c", (p[i + j] < ' ' || p[i + j] > 0x7f) ? '.' :
p[i + j]);
+ fprintf(stderr, "\n");
}
- return 0;
}
-static void print_direntry(direntry_t* direntry)
+static void print_direntry(const direntry_t* direntry)
{
+ int j = 0;
+ char buffer[1024];
+
+ fprintf(stderr, "direntry 0x%x: ", (int)direntry);
if(!direntry)
return;
- if(direntry->attributes==0xf) {
+ if(is_long_name(direntry)) {
unsigned char* c=(unsigned char*)direntry;
int i;
for(i=1;i<11 && c[i] && c[i]!=0xff;i+=2)
- fputc(c[i],stderr);
+#define ADD_CHAR(c) {buffer[j] = (c); if (buffer[j] < ' ') buffer[j] = '°';
j++;}
+ ADD_CHAR(c[i]);
for(i=14;i<26 && c[i] && c[i]!=0xff;i+=2)
- fputc(c[i],stderr);
+ ADD_CHAR(c[i]);
for(i=28;i<32 && c[i] && c[i]!=0xff;i+=2)
- fputc(c[i],stderr);
- fputc('\n',stderr);
+ ADD_CHAR(c[i]);
+ buffer[j] = 0;
+ fprintf(stderr, "%s\n", buffer);
} else {
int i;
for(i=0;i<11;i++)
- fputc(direntry->name[i],stderr);
- fprintf(stderr,"attributes=0x%02x begin=%d size=%d\n",
+ ADD_CHAR(direntry->name[i]);
+ buffer[j] = 0;
+ fprintf(stderr,"%s attributes=0x%02x begin=%d size=%d\n",
+ buffer,
direntry->attributes,
- direntry->begin,direntry->size);
+ begin_of_direntry(direntry),le32_to_cpu(direntry->size));
}
}
-static void print_changed_sector(BlockDriverState *bs,int64_t sector_num,const
uint8_t *buf)
+static void print_mapping(const mapping_t* mapping)
{
- BDRVVVFATState *s = bs->opaque;
+ fprintf(stderr, "mapping (0x%x): begin, end = %d, %d, dir_index = %d,
first_mapping_index = %d, name = %s, mode = 0x%x, " , (int)mapping,
mapping->begin, mapping->end, mapping->dir_index, mapping->first_mapping_index,
mapping->path, mapping->mode);
+ if (mapping->mode & MODE_DIRECTORY)
+ fprintf(stderr, "parent_mapping_index = %d, first_dir_index = %d\n",
mapping->info.dir.parent_mapping_index, mapping->info.dir.first_dir_index);
+ else
+ fprintf(stderr, "offset = %d\n", mapping->info.file.offset);
+}
+#endif
- if(sector_num<s->first_sectors_number)
- return;
- if(sector_num<s->first_sectors_number+s->sectors_per_fat*2) {
- int first=((sector_num-s->first_sectors_number)%s->sectors_per_fat);
- int first_fat_entry=first*0x200/2;
- int i;
+static int vvfat_read(BlockDriverState *bs, int64_t sector_num,
+ uint8_t *buf, int nb_sectors)
+{
+ BDRVVVFATState *s = bs->opaque;
+ int i;
- fprintf(stderr, "fat:\n");
- for(i=0;i<0x200;i+=2) {
- uint16_t* f=array_get(&(s->fat),first_fat_entry+i/2);
- if(memcmp(buf+i,f,2))
- fprintf(stderr,"%d(%d->%d)
",first_fat_entry+i/2,*f,*(uint16_t*)(buf+i));
+ for(i=0;i<nb_sectors;i++,sector_num++) {
+ if (sector_num >= s->sector_count)
+ return -1;
+ if (s->qcow) {
+ int n;
+ if (s->qcow->drv->bdrv_is_allocated(s->qcow,
+ sector_num, nb_sectors-i, &n)) {
+DLOG(fprintf(stderr, "sectors %d+%d allocated\n", (int)sector_num, n));
+ if (s->qcow->drv->bdrv_read(s->qcow, sector_num, buf+i*0x200,
n))
+ return -1;
+ i += n - 1;
+ sector_num += n - 1;
+ continue;
+ }
+DLOG(fprintf(stderr, "sector %d not allocated\n", (int)sector_num));
}
- fprintf(stderr, "\n");
- } else if(sector_num<s->faked_sectors) {
- direntry_t* d=(direntry_t*)buf;
- int i;
- fprintf(stderr, "directory:\n");
- for(i=0;i<0x200/sizeof(direntry_t);i++) {
- direntry_t*
d_old=(direntry_t*)(s->directory.pointer+0x200*(sector_num-s->first_sectors_number-s->sectors_per_fat*2)+i*sizeof(direntry_t));
- if(memcmp(d+i,d_old,sizeof(direntry_t))) {
- fprintf(stderr, "old: "); print_direntry(d_old);
- fprintf(stderr, "new: "); print_direntry(d+i);
- fprintf(stderr, "\n");
+ if(sector_num<s->faked_sectors) {
+ if(sector_num<s->first_sectors_number)
+ memcpy(buf+i*0x200,&(s->first_sectors[sector_num*0x200]),0x200);
+ else if(sector_num-s->first_sectors_number<s->sectors_per_fat)
+
memcpy(buf+i*0x200,&(s->fat.pointer[(sector_num-s->first_sectors_number)*0x200]),0x200);
+ else
if(sector_num-s->first_sectors_number-s->sectors_per_fat<s->sectors_per_fat)
+
memcpy(buf+i*0x200,&(s->fat.pointer[(sector_num-s->first_sectors_number-s->sectors_per_fat)*0x200]),0x200);
+ } else {
+ uint32_t sector=sector_num-s->faked_sectors,
+ sector_offset_in_cluster=(sector%s->sectors_per_cluster),
+ cluster_num=sector/s->sectors_per_cluster;
+ if(read_cluster(s, cluster_num) != 0) {
+ /* LATER TODO: strict: return -1; */
+ memset(buf+i*0x200,0,0x200);
+ continue;
}
+ memcpy(buf+i*0x200,s->cluster+sector_offset_in_cluster*0x200,0x200);
}
- } else {
- int sec=(sector_num-s->first_sectors_number-2*s->sectors_per_fat);
- fprintf(stderr, "\tcluster: %d(+%d
sectors)\n",sec/s->sectors_per_cluster,sec%s->sectors_per_cluster);
}
+ return 0;
}
-char direntry_is_free(const direntry_t* direntry)
-{
- return direntry->name[0]==0 || direntry->name[0]==0xe5;
-}
+/* LATER TODO: statify all functions */
-/* TODO: use this everywhere */
-static inline uint32_t begin_of_direntry(direntry_t* direntry)
-{
- return le16_to_cpu(direntry->begin)|(le16_to_cpu(direntry->begin_hi)<<16);
-}
+/*
+ * Idea of the write support (use snapshot):
+ *
+ * 1. check if all data is consistent, recording renames, modifications,
+ * new files and directories (in s->commits).
+ *
+ * 2. if the data is not consistent, stop committing
+ *
+ * 3. handle renames, and create new files and directories (do not yet
+ * write their contents)
+ *
+ * 4. walk the directories, fixing the mapping and direntries, and marking
+ * the handled mappings as not deleted
+ *
+ * 5. commit the contents of the files
+ *
+ * 6. handle deleted files and directories
+ *
+ */
-int consistency_check1(BDRVVVFATState *s) {
- /* check all mappings */
+typedef struct commit_t {
+ char* path;
+ union {
+ struct { uint32_t cluster; } rename;
+ struct { int dir_index; uint32_t modified_offset; } writeout;
+ struct { uint32_t first_cluster; } new_file;
+ struct { uint32_t cluster; } mkdir;
+ } param;
+ /* DELETEs and RMDIRs are handled differently: see handle_deletes() */
+ enum {
+ ACTION_RENAME, ACTION_WRITEOUT, ACTION_NEW_FILE, ACTION_MKDIR
+ } action;
+} commit_t;
+
+static void clear_commits(BDRVVVFATState* s)
+{
int i;
- for(i=0;i<s->mapping.next;i++) {
- mapping_t* mapping=array_get(&(s->mapping),i);
- int j;
- for(j=mapping->begin;j<mapping->end-1;j++)
- assert(fat_get(s,j)==j+1);
- assert(fat_get(s,j)==(0x7fffffff&s->max_fat_value));
+DLOG(fprintf(stderr, "clear_commits (%d commits)\n", s->commits.next));
+ for (i = 0; i < s->commits.next; i++) {
+ commit_t* commit = array_get(&(s->commits), i);
+ assert(commit->path || commit->action == ACTION_WRITEOUT);
+ if (commit->action != ACTION_WRITEOUT) {
+ assert(commit->path);
+ free(commit->path);
+ } else
+ assert(commit->path == NULL);
}
- return 0;
+ s->commits.next = 0;
}
-int consistency_check2(BDRVVVFATState *s) {
- /* check fat entries: consecutive fat entries should be mapped in one
mapping */
- int i;
- /* TODO: i=0 (mappings for direntries have to be sorted) */
- for(i=s->sectors_for_directory/s->sectors_per_cluster;i<s->fat.next-1;i++)
{
- uint32_t j=fat_get(s,i);
- if(j!=i+1 && j!=0 && !fat_eof(s,j)) {
- mapping_t* mapping=find_mapping_for_cluster(s,i+1);
- assert(mapping->begin==i+1);
- }
- }
- return 0;
+static void schedule_rename(BDRVVVFATState* s,
+ uint32_t cluster, char* new_path)
+{
+ commit_t* commit = array_get_next(&(s->commits));
+ commit->path = new_path;
+ commit->param.rename.cluster = cluster;
+ commit->action = ACTION_RENAME;
}
-int consistency_check3(BDRVVVFATState *s) {
- /* check that for each file there is exactly one mapping per cluster */
- int i,count_non_next=0;
- for(i=0;i<s->mapping.next;i++) {
- mapping_t* mapping=array_get(&(s->mapping),i);
- /* TODO: when directories are correctly adapted, add them here */
- assert(mapping->begin<mapping->end);
- if(mapping->mode==MODE_NORMAL) {
- int j,count=0,count_next=0;
- for(j=0;j<s->mapping.next;j++) {
- mapping_t* other=array_get(&(s->mapping),j);
- if(mapping->begin<other->end&&mapping->end>other->begin)
- count++;
- if(mapping->end==other->begin)
- count_next++;
- }
- assert(count==1); /* no overlapping mappings */
- assert(count_next==1 || count_next==0); /* every mapping except the
last one has a successor */
- if(!count_next)
- count_non_next++;
- }
- }
- assert(count_non_next==1); /* only one last mapping */
- return 0;
+static void schedule_writeout(BDRVVVFATState* s,
+ int dir_index, uint32_t modified_offset)
+{
+ commit_t* commit = array_get_next(&(s->commits));
+ commit->path = NULL;
+ commit->param.writeout.dir_index = dir_index;
+ commit->param.writeout.modified_offset = modified_offset;
+ commit->action = ACTION_WRITEOUT;
}
-static inline commit_t* commit_get_next(BDRVVVFATState* s)
+static void schedule_new_file(BDRVVVFATState* s,
+ char* path, uint32_t first_cluster)
{
- commit_t* commit=array_get_next(&(s->commit));
- if((commit->buf=malloc(s->cluster_size))==0) {
- /* out of memory */
- s->commit.next--;
- return 0;
- }
- return commit;
+ commit_t* commit = array_get_next(&(s->commits));
+ commit->path = path;
+ commit->param.new_file.first_cluster = first_cluster;
+ commit->action = ACTION_NEW_FILE;
}
-int commit_remove(BDRVVVFATState* s,commit_t* commit)
+static void schedule_mkdir(BDRVVVFATState* s, uint32_t cluster, char* path)
{
- int index=commit-(commit_t*)s->commit.pointer;
- free(commit->buf);
- if(array_roll(&(s->commit),s->commit.next-1,index,1))
- return -1;
- s->commit.next--;
- return 0;
+ commit_t* commit = array_get_next(&(s->commits));
+ commit->path = path;
+ commit->param.mkdir.cluster = cluster;
+ commit->action = ACTION_MKDIR;
}
-/* TODO: the plan for write support:
- *
- * it seems that the direntries are written first, then the data is committed
- * to the free sectors, then fat 1 is updated, then fat2.
- *
- * Plan: when sectors are written, do the following:
- *
- * - if they are in a directory, check if the entry has changed. if yes,
- * look what has changed (different strategies for name, begin & size).
- *
- * if it is new (old entry is only 0's or has E5 at the start), create it,
- * and also create mapping, but in a special mode "undefined" (TODO),
- * because we cannot know which clusters belong to it yet.
- *
- * if it is zeroed, or has E5 at the start, look if has just moved. If yes,
- * copy the entry to the new position. If no, delete the file.
- *
- * - if they are in data, and the cluster is undefined, add it to the commit
- * list. if the cluster is defined (find_mapping), then write it into the
- * corresponding file.
- *
- * If it is the last cluster (TODO: add a function
- * fat_get(s,cluster); ), make sure not to write a complete cluster_size.
- *
- * If the data is in current_cluster, update s->cluster.
- *
- * - if they are in fat 1, update mappings, look in the commit list
- * (assertions!) and if the cluster is now known (or changed from undefined
- * state to defined state, like when begin or size changed in a direntry),
- * write it.
- *
- * - if they are in fat 2, make sure they match with current fat.
- *
- */
+typedef struct {
+ unsigned char name[1024];
+ int checksum, len;
+ int sequence_number;
+} long_file_name;
-void mapping_modify_from_direntry(BDRVVVFATState* s,mapping_t*
mapping,direntry_t* direntry)
+static void lfn_init(long_file_name* lfn)
{
- int begin=le16_to_cpu(direntry->begin),
- end=begin+le32_to_cpu(direntry->size)/s->cluster_size+1,
- i;
- mapping->mode = MODE_MODIFIED;
- /* TODO: what if begin==0 (size==0)? */
- mapping->begin = begin;
- /* TODO: why not just mapping->end = begin+1 ? */
- for(i=begin+1;i<end && (fat_get(s,i)==0 || fat_get(s,i)==i+1);i++);
- mapping->end = i;
+ lfn->sequence_number = lfn->len = 0;
+ lfn->checksum = 0x100;
}
-mapping_t* find_mapping_for_direntry(BDRVVVFATState* s,direntry_t* direntry)
+/* return 0 if parsed successfully, > 0 if no long name, < 0 if error */
+static int parse_long_name(long_file_name* lfn,
+ const direntry_t* direntry)
{
- int i;
- int dir_index=direntry-((direntry_t*)s->directory.pointer);
-
- /* TODO: support allocation for new clusters for directories (new/larger
directory */
- assert(dir_index<0x200/0x20*s->sectors_for_directory);
-
- for(i=0;i<s->mapping.next;i++) {
- mapping_t* mapping=array_get(&(s->mapping),i);
- if(mapping->dir_index==dir_index && mapping->offset==0 &&
- mapping->mode!=MODE_UNDEFINED)
- return mapping;
+ int i, j, offset;
+ const unsigned char* pointer = (const unsigned char*)direntry;
+
+ if (!is_long_name(direntry))
+ return 1;
+
+ if (pointer[0] & 0x40) {
+ lfn->sequence_number = pointer[0] & 0x3f;
+ lfn->checksum = pointer[13];
+ lfn->name[0] = 0;
+ } else if ((pointer[0] & 0x3f) != --lfn->sequence_number)
+ return -1;
+ else if (pointer[13] != lfn->checksum)
+ return -2;
+ else if (pointer[12] || pointer[26] || pointer[27])
+ return -3;
+
+ offset = 13 * (lfn->sequence_number - 1);
+ for (i = 0, j = 1; i < 13; i++, j+=2) {
+ if (j == 11)
+ j = 14;
+ else if (j == 26)
+ j = 28;
+
+ if (pointer[j+1] == 0)
+ lfn->name[offset + i] = pointer[j];
+ else if (pointer[j+1] != 0xff || (pointer[0] & 0x40) == 0)
+ return -4;
+ else
+ lfn->name[offset + i] = 0;
}
+
+ if (pointer[0] & 0x40)
+ lfn->len = offset + strlen(lfn->name + offset);
+
return 0;
}
-static inline uint32_t sector2cluster(BDRVVVFATState* s,off_t sector_num)
+/* returns 0 if successful, >0 if no short_name, and <0 on error */
+static int parse_short_name(BDRVVVFATState* s,
+ long_file_name* lfn, direntry_t* direntry)
{
- return
(sector_num-s->first_sectors_number-2*s->sectors_per_fat)/s->sectors_per_cluster;
-}
+ int i, j;
-static inline uint32_t sector_offset_in_cluster(BDRVVVFATState* s,off_t
sector_num)
-{
- return
(sector_num-s->first_sectors_number-2*s->sectors_per_fat)%s->sectors_per_cluster;
-}
+ if (!is_short_name(direntry))
+ return 1;
-static commit_t* get_commit_for_cluster(BDRVVVFATState* s,uint32_t cluster_num)
-{
- int i;
- for(i=0;i<s->commit.next;i++) {
- commit_t* commit=array_get(&(s->commit),i);
- if(commit->cluster_num==cluster_num)
- return commit;
+ for (j = 7; j >= 0 && direntry->name[j] == ' '; j--);
+ for (i = 0; i <= j; i++) {
+ if (direntry->name[i] <= ' ' || direntry->name[i] > 0x7f)
+ return -1;
+ else if (s->downcase_short_names)
+ lfn->name[i] = tolower(direntry->name[i]);
+ else
+ lfn->name[i] = direntry->name[i];
}
+
+ for (j = 2; j >= 0 && direntry->extension[j] == ' '; j--);
+ if (j >= 0) {
+ lfn->name[i++] = '.';
+ lfn->name[i + j + 1] = '\0';
+ for (;j >= 0; j--) {
+ if (direntry->extension[j] <= ' ' || direntry->extension[j] > 0x7f)
+ return -2;
+ else if (s->downcase_short_names)
+ lfn->name[i + j] = tolower(direntry->extension[j]);
+ else
+ lfn->name[i + j] = direntry->extension[j];
+ }
+ } else
+ lfn->name[i + j + 1] = '\0';
+
+ lfn->len = strlen(lfn->name);
+
return 0;
}
-static inline commit_t* create_or_get_commit_for_sector(BDRVVVFATState*
s,off_t sector_num)
+static inline uint32_t modified_fat_get(BDRVVVFATState* s,
+ unsigned int cluster)
{
- int i;
- commit_t* commit;
- uint32_t cluster_num=sector2cluster(s,sector_num);
-
- for(i=0;i<s->commit.next;i++) {
- commit=array_get(&(s->commit),i);
- if(commit->cluster_num==cluster_num)
- return commit;
+ if (cluster < s->last_cluster_of_root_directory) {
+ if (cluster + 1 == s->last_cluster_of_root_directory)
+ return s->max_fat_value;
+ else
+ return cluster + 1;
}
- commit=commit_get_next(s);
- commit->cluster_num=cluster_num;
- /* we can ignore read errors here */
- read_cluster(s,cluster_num);
- memcpy(commit->buf,s->cluster,s->cluster_size);
- return commit;
+ if (s->fat_type==32) {
+ uint32_t* entry=((uint32_t*)s->fat2)+cluster;
+ return le32_to_cpu(*entry);
+ } else if (s->fat_type==16) {
+ uint16_t* entry=((uint16_t*)s->fat2)+cluster;
+ return le16_to_cpu(*entry);
+ } else {
+ const uint8_t* x=s->fat2+cluster*3/2;
+ return ((x[0]|(x[1]<<8))>>(cluster&1?4:0))&0x0fff;
+ }
}
-static direntry_t* get_direntry_for_mapping(BDRVVVFATState* s,mapping_t*
mapping)
+static inline int cluster_was_modified(BDRVVVFATState* s, uint32_t cluster_num)
{
- if(mapping->mode==MODE_UNDEFINED)
- return 0;
- if(mapping->dir_index>=0x200/0x20*s->sectors_for_directory)
+ int was_modified = 0;
+ int i, dummy;
+
+ if (s->qcow == NULL)
return 0;
- return
(direntry_t*)(s->directory.pointer+sizeof(direntry_t)*mapping->dir_index);
+
+ for (i = 0; !was_modified && i < s->sectors_per_cluster; i++)
+ was_modified = s->qcow->drv->bdrv_is_allocated(s->qcow,
+ cluster2sector(s, cluster_num) + i, 1, &dummy);
+
+ return was_modified;
}
-static void print_mappings(BDRVVVFATState* s)
+static const char* get_basename(const char* path)
{
- int i;
- fprintf(stderr,"mapping:\n");
- for(i=0;i<s->mapping.next;i++) {
- mapping_t* m=array_get(&(s->mapping),i);
- direntry_t* d=get_direntry_for_mapping(s,m);
- fprintf(stderr,"%02d %d-%d (%d) %s (dir:
%d)",i,(int)m->begin,(int)m->end,(int)m->offset,m->filename,m->dir_index);
- print_direntry(d);
- fprintf(stderr,"\n");
- }
- fprintf(stderr,"mappings end.\n");
+ char* basename = strrchr(path, '/');
+ if (basename == NULL)
+ return path;
+ else
+ return basename + 1; /* strip '/' */
}
-/* TODO: statify all functions */
+/*
+ * The array s->used_clusters holds the states of the clusters. If it is
+ * part of a file, it has bit 2 set, in case of a directory, bit 1. If it
+ * was modified, bit 3 is set.
+ * If any cluster is allocated, but not part of a file or directory, this
+ * driver refuses to commit.
+ */
+typedef enum {
+ USED_DIRECTORY = 1, USED_FILE = 2, USED_ANY = 3, USED_ALLOCATED = 4
+} used_t;
-/* This function is only meant for file contents.
- * It will return an error if used for other sectors. */
-static int write_cluster(BDRVVVFATState* s,uint32_t cluster_num,const uint8_t*
buf)
+/*
+ * get_cluster_count_for_direntry() not only determines how many clusters
+ * are occupied by direntry, but also if it was renamed or modified.
+ *
+ * A file is thought to be renamed *only* if there already was a file with
+ * exactly the same first cluster, but a different name.
+ *
+ * Further, the files/directories handled by this function are
+ * assumed to be *not* deleted (and *only* those).
+ */
+static uint32_t get_cluster_count_for_direntry(BDRVVVFATState* s,
+ direntry_t* direntry, const char* path)
{
- /* sector_offset is the sector_num relative to the first cluster */
- mapping_t* mapping=find_mapping_for_cluster(s,cluster_num);
- direntry_t* direntry;
- int next_cluster,write_size,last_cluster;
- off_t offset;
+ /*
+ * This is a little bit tricky:
+ * IF the guest OS just inserts a cluster into the file chain,
+ * and leaves the rest alone, (i.e. the original file had clusters
+ * 15 -> 16, but now has 15 -> 32 -> 16), then the following happens:
+ *
+ * - do_commit will write the cluster into the file at the given
+ * offset, but
+ *
+ * - the cluster which is overwritten should be moved to a later
+ * position in the file.
+ *
+ * I am not aware that any OS does something as braindead, but this
+ * situation could happen anyway when not committing for a long time.
+ * Just to be sure that this does not bite us, detect it, and copy the
+ * contents of the clusters to-be-overwritten into the qcow.
+ */
+ int copy_it = 0;
+ int was_modified = 0;
+ int32_t ret = 0;
+
+ uint32_t cluster_num = begin_of_direntry(direntry);
+ uint32_t offset = 0;
+ int first_mapping_index = -1;
+ mapping_t* mapping = NULL;
+ const char* basename2 = NULL;
- /* if this cluster is free, return error */
- next_cluster=fat_get(s,cluster_num);
- if(next_cluster<2)
- return -1;
-
- /* TODO: MODE_DIRECTORY */
- if(!mapping || mapping->mode==MODE_UNDEFINED ||
mapping->mode==MODE_DIRECTORY)
- return -1;
- direntry=get_direntry_for_mapping(s,mapping);
- if(!direntry)
- return -2;
+ vvfat_close_current_file(s);
- /* get size to write */
- last_cluster=fat_eof(s,next_cluster);
- write_size=!last_cluster?s->cluster_size:
- (le32_to_cpu(direntry->size)%s->cluster_size);
- if(write_size<=0)
+ /* the root directory */
+ if (cluster_num == 0)
return 0;
- //fprintf(stderr,"next_cluster: %d (%d), write_size: %d, %d,
%d\n",next_cluster,s->max_fat_value-8,write_size,direntry->size,s->cluster_size);
- if(open_file(s,mapping,O_RDWR))
- return -4;
-
- offset=(cluster_num-mapping->begin+mapping->offset)*s->cluster_size;
- if(lseek(s->current_fd,offset,SEEK_SET)!=offset)
- return -3;
- if(write(s->current_fd,buf,write_size)!=write_size) {
- lseek(s->current_fd,0,SEEK_END);
- vvfat_close_current_file(s);
- return -2;
- }
+ /* write support */
+ if (s->qcow) {
+ basename2 = get_basename(path);
- /* seek to end of file, so it doesn't get truncated */
- if(!last_cluster)
- lseek(s->current_fd,0,SEEK_END);
- else {
- ftruncate(s->current_fd,le32_to_cpu(direntry->size));
- vvfat_close_current_file(s);
+ mapping = find_mapping_for_cluster(s, cluster_num);
+
+ if (mapping) {
+ assert(mapping->mode & MODE_DELETED);
+ mapping->mode &= ~MODE_DELETED;
+
+ const char* basename = get_basename(mapping->path);
+
+ assert(mapping->mode & MODE_NORMAL);
+
+ /* rename */
+ if (strcmp(basename, basename2))
+ schedule_rename(s, cluster_num, strdup(path));
+ } else if (is_file(direntry))
+ /* new file */
+ schedule_new_file(s, strdup(path), cluster_num);
+ else {
+ assert(0);
+ return 0;
+ }
}
- /* update s->cluster if necessary */
- if(cluster_num==s->current_cluster && s->cluster!=buf)
- memcpy(s->cluster,buf,s->cluster_size);
+ while(1) {
+ if (s->qcow) {
+ if (!copy_it && cluster_was_modified(s, cluster_num)) {
+ if (mapping == NULL ||
+ mapping->begin > cluster_num ||
+ mapping->end <= cluster_num)
+ mapping = find_mapping_for_cluster(s, cluster_num);
- return 0;
+
+ if (mapping &&
+ (mapping->mode & MODE_DIRECTORY) == 0) {
+
+ /* was modified in qcow */
+ if (offset != mapping->info.file.offset + s->cluster_size
+ * (cluster_num - mapping->begin)) {
+ /* offset of this cluster in file chain has changed */
+ assert(0);
+ copy_it = 1;
+ } else if (offset == 0) {
+ const char* basename = get_basename(mapping->path);
+
+ if (strcmp(basename, basename2))
+ copy_it = 1;
+ first_mapping_index = array_index(&(s->mapping),
mapping);
+ }
+
+ if (mapping->first_mapping_index != first_mapping_index
+ && mapping->info.file.offset > 0) {
+ assert(0);
+ copy_it = 1;
+ }
+
+ /* need to write out? */
+ if (!was_modified && is_file(direntry)) {
+ was_modified = 1;
+ schedule_writeout(s, mapping->dir_index, offset);
+ }
+ }
+ }
+
+ if (copy_it) {
+ int i, dummy;
+ /*
+ * This is horribly inefficient, but that is okay, since
+ * it is rarely executed, if at all.
+ */
+ int64_t offset = cluster2sector(s, cluster_num);
+
+ vvfat_close_current_file(s);
+ for (i = 0; i < s->sectors_per_cluster; i++)
+ if (!s->qcow->drv->bdrv_is_allocated(s->qcow,
+ offset + i, 1, &dummy)) {
+ if (vvfat_read(s->bs,
+ offset, s->cluster_buffer, 1))
+ return -1;
+ if (s->qcow->drv->bdrv_write(s->qcow,
+ offset, s->cluster_buffer, 1))
+ return -2;
+ }
+ }
+ }
+
+ ret++;
+ if (s->used_clusters[cluster_num] & USED_ANY)
+ return 0;
+ s->used_clusters[cluster_num] = USED_FILE;
+
+ cluster_num = modified_fat_get(s, cluster_num);
+
+ if (fat_eof(s, cluster_num))
+ return ret;
+ else if (cluster_num < 2 || cluster_num > s->max_fat_value - 16)
+ return -1;
+
+ offset += s->cluster_size;
+ }
}
-/* this function returns !=0 on error */
-int mapping_is_consistent(BDRVVVFATState* s,mapping_t* mapping)
+/*
+ * This function looks at the modified data (qcow).
+ * It returns 0 upon inconsistency or error, and the number of clusters
+ * used by the directory, its subdirectories and their files.
+ */
+static int check_directory_consistency(BDRVVVFATState *s,
+ int cluster_num, const char* path)
{
- direntry_t* direntry=get_direntry_for_mapping(s,mapping);
- uint32_t cluster_count=0;
- int commit_count=0; /* number of commits for this file (we also write
incomplete files; think "append") */
- //fprintf(stderr,"check direntry for %s\n",mapping->filename);
- while(mapping) {
+ int ret = 0;
+ unsigned char* cluster = malloc(s->cluster_size);
+ direntry_t* direntries = (direntry_t*)cluster;
+ mapping_t* mapping = find_mapping_for_cluster(s, cluster_num);
+
+ long_file_name lfn;
+ int path_len = strlen(path);
+ char path2[PATH_MAX];
+
+ assert(path_len < PATH_MAX); /* len was tested before! */
+ strcpy(path2, path);
+ path2[path_len] = '/';
+ path2[path_len + 1] = '\0';
+
+ if (mapping) {
+ const char* basename = get_basename(mapping->path);
+ const char* basename2 = get_basename(path);
+
+ assert(mapping->mode & MODE_DIRECTORY);
+
+ assert(mapping->mode & MODE_DELETED);
+ mapping->mode &= ~MODE_DELETED;
+
+ if (strcmp(basename, basename2))
+ schedule_rename(s, cluster_num, strdup(path));
+ } else
+ /* new directory */
+ schedule_mkdir(s, cluster_num, strdup(path));
+
+ lfn_init(&lfn);
+ do {
int i;
- assert(mapping->begin<mapping->end);
- for(i=mapping->begin;i<mapping->end-1;i++) {
- if(i<=0 || fat_get(s,i)!=i+1) {
- /*fprintf(stderr,"the fat mapping of %d is not %d, but %d\n",
- i,i+1,fat_get(s,i));*/
- return -1;
+ int subret = 0;
+
+ ret++;
+
+ if (s->used_clusters[cluster_num] & USED_ANY) {
+ fprintf(stderr, "cluster %d used more than once\n",
(int)cluster_num);
+ return 0;
+ }
+ s->used_clusters[cluster_num] = USED_DIRECTORY;
+
+DLOG(fprintf(stderr, "read cluster %d (sector %d)\n", (int)cluster_num,
(int)cluster2sector(s, cluster_num)));
+ subret = vvfat_read(s->bs, cluster2sector(s, cluster_num), cluster,
+ s->sectors_per_cluster);
+ if (subret) {
+ fprintf(stderr, "Error fetching direntries\n");
+ fail:
+ free(cluster);
+ return 0;
+ }
+
+ for (i = 0; i < 0x10 * s->sectors_per_cluster; i++) {
+ int cluster_count;
+
+DLOG(fprintf(stderr, "check direntry %d: \n", i); print_direntry(direntries +
i));
+ if (is_volume_label(direntries + i) || is_dot(direntries + i) ||
+ is_free(direntries + i))
+ continue;
+
+ subret = parse_long_name(&lfn, direntries + i);
+ if (subret < 0) {
+ fprintf(stderr, "Error in long name\n");
+ goto fail;
+ }
+ if (subret == 0 || is_free(direntries + i))
+ continue;
+
+ if (fat_chksum(direntries+i) != lfn.checksum) {
+ subret = parse_short_name(s, &lfn, direntries + i);
+ if (subret < 0) {
+ fprintf(stderr, "Error in short name (%d)\n", subret);
+ goto fail;
+ }
+ if (subret > 0 || !strcmp(lfn.name, ".")
+ || !strcmp(lfn.name, ".."))
+ continue;
+ }
+ lfn.checksum = 0x100; /* cannot use long name twice */
+
+ if (path_len + 1 + lfn.len >= PATH_MAX) {
+ fprintf(stderr, "Name too long: %s/%s\n", path, lfn.name);
+ goto fail;
}
- if(get_commit_for_cluster(s,i))
- commit_count++;
+ strcpy(path2 + path_len + 1, lfn.name);
+
+ if (is_directory(direntries + i)) {
+ if (begin_of_direntry(direntries + i) == 0) {
+ DLOG(fprintf(stderr, "invalid begin for directory: %s\n",
path2); print_direntry(direntries + i));
+ goto fail;
+ }
+ cluster_count = check_directory_consistency(s,
+ begin_of_direntry(direntries + i), path2);
+ if (cluster_count == 0) {
+ DLOG(fprintf(stderr, "problem in directory %s:\n", path2);
print_direntry(direntries + i));
+ goto fail;
+ }
+ } else if (is_file(direntries + i)) {
+ /* check file size with FAT */
+ cluster_count = get_cluster_count_for_direntry(s, direntries +
i, path2);
+ if (cluster_count !=
+ (le32_to_cpu(direntries[i].size) + s->cluster_size
+ - 1) / s->cluster_size) {
+ DLOG(fprintf(stderr, "Cluster count mismatch\n"));
+ goto fail;
+ }
+ } else
+ assert(0); /* cluster_count = 0; */
+
+ ret += cluster_count;
}
- if(get_commit_for_cluster(s,i))
- commit_count++;
- cluster_count+=mapping->end-mapping->begin;
-
- i=fat_get(s,mapping->end-1);
- if(fat_eof(s,i))
- break;
+ cluster_num = modified_fat_get(s, cluster_num);
+ } while(!fat_eof(s, cluster_num));
- mapping=find_mapping_for_cluster(s,i);
- if(!mapping) {
- //fprintf(stderr,"No mapping found for %d\n",i);
- print_mappings(s);
- return -2;
+ free(cluster);
+ return ret;
+}
+
+/* returns 1 on success */
+static int is_consistent(BDRVVVFATState* s)
+{
+ int i, check;
+ int used_clusters_count = 0;
+
+DLOG(checkpoint());
+ /*
+ * - get modified FAT
+ * - compare the two FATs (TODO)
+ * - get buffer for marking used clusters
+ * - recurse direntries from root (using bs->bdrv_read to make
+ * sure to get the new data)
+ * - check that the FAT agrees with the size
+ * - count the number of clusters occupied by this directory and
+ * its files
+ * - check that the cumulative used cluster count agrees with the
+ * FAT
+ * - if all is fine, return number of used clusters
+ */
+ if (s->fat2 == NULL) {
+ int size = 0x200 * s->sectors_per_fat;
+ s->fat2 = malloc(size);
+ memcpy(s->fat2, s->fat.pointer, size);
+ }
+ check = vvfat_read(s->bs,
+ s->first_sectors_number, s->fat2, s->sectors_per_fat);
+ if (check) {
+ fprintf(stderr, "Could not copy fat\n");
+ return 0;
+ }
+ assert (s->used_clusters);
+ for (i = 0; i < sector2cluster(s, s->sector_count); i++)
+ s->used_clusters[i] &= ~USED_ANY;
+
+ clear_commits(s);
+
+ /* mark every mapped file/directory as deleted.
+ * (check_directory_consistency() will unmark those still present). */
+ if (s->qcow)
+ for (i = 0; i < s->mapping.next; i++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+ if (mapping->first_mapping_index < 0)
+ mapping->mode |= MODE_DELETED;
+ }
+
+ used_clusters_count = check_directory_consistency(s, 0, s->path);
+ if (used_clusters_count <= 0) {
+ DLOG(fprintf(stderr, "problem in directory\n"));
+ return 0;
+ }
+
+ check = s->last_cluster_of_root_directory;
+ for (i = check; i < sector2cluster(s, s->sector_count); i++) {
+ if (modified_fat_get(s, i)) {
+ if(!s->used_clusters[i]) {
+ DLOG(fprintf(stderr, "FAT was modified (%d), but cluster is not
used?\n", i));
+ return 0;
+ }
+ check++;
+ }
+
+ if (s->used_clusters[i] == USED_ALLOCATED) {
+ /* allocated, but not used... */
+ DLOG(fprintf(stderr, "unused, modified cluster: %d\n", i));
+ return 0;
}
}
-
if(cluster_count!=(le32_to_cpu(direntry->size)+s->cluster_size-1)/s->cluster_size)
{
- //fprintf(stderr,"cluster_count is %d, but size is
%d\n",cluster_count,le32_to_cpu(direntry->size));
- return -3;
+ if (check != used_clusters_count)
+ return 0;
+
+ return used_clusters_count;
+}
+
+static inline void adjust_mapping_indices(BDRVVVFATState* s,
+ int offset, int adjust)
+{
+ int i;
+
+ for (i = 0; i < s->mapping.next; i++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+
+#define ADJUST_MAPPING_INDEX(name) \
+ if (mapping->name >= offset) \
+ mapping->name += adjust
+
+ ADJUST_MAPPING_INDEX(first_mapping_index);
+ if (mapping->mode & MODE_DIRECTORY)
+ ADJUST_MAPPING_INDEX(info.dir.parent_mapping_index);
}
+}
- if(commit_count==0)
- return -4;
+/* insert or update mapping */
+static mapping_t* insert_mapping(BDRVVVFATState* s,
+ uint32_t begin, uint32_t end)
+{
+ /*
+ * - find mapping where mapping->begin >= begin,
+ * - if mapping->begin > begin: insert
+ * - adjust all references to mappings!
+ * - else: adjust
+ * - replace name
+ */
+ int index = find_mapping_for_cluster_aux(s, begin, 0, s->mapping.next);
+ mapping_t* mapping = NULL;
+ mapping_t* first_mapping = array_get(&(s->mapping), 0);
+
+ if (index < s->mapping.next && (mapping = array_get(&(s->mapping), index))
+ && mapping->begin < begin) {
+ mapping->end = begin;
+ index++;
+ mapping = array_get(&(s->mapping), index);
+ }
+ if (index >= s->mapping.next || mapping->begin > begin) {
+ mapping = array_insert(&(s->mapping), index, 1);
+ mapping->path = NULL;
+ adjust_mapping_indices(s, index, +1);
+ }
- //fprintf(stderr,"okay\n");
- return 0;
+ mapping->begin = begin;
+ mapping->end = end;
+
+DLOG(mapping_t* next_mapping;
+assert(index + 1 >= s->mapping.next ||
+((next_mapping = array_get(&(s->mapping), index + 1)) &&
+ next_mapping->begin >= end)));
+
+ if (s->current_mapping && first_mapping != (mapping_t*)s->mapping.pointer)
+ s->current_mapping = array_get(&(s->mapping),
+ s->current_mapping - first_mapping);
+
+ return mapping;
}
-/* TODO: remember what comes third, and what's first in this OS:
- * FAT, direntry or data.
- * If the last written sector is either last in cluster or
sector_num+nb_sectors-1,
- * - commit every cluster for this file if mapping_is_consistent()==0
- * - if the last written sector is first_action, and
last_action=third_action, clear commit
- */
+static int remove_mapping(BDRVVVFATState* s, int mapping_index)
+{
+ mapping_t* mapping = array_get(&(s->mapping), mapping_index);
+ mapping_t* first_mapping = array_get(&(s->mapping), 0);
+
+ /* free mapping */
+ if (mapping->first_mapping_index < 0)
+ free(mapping->path);
+
+ /* remove from s->mapping */
+ array_remove(&(s->mapping), mapping_index);
-static int commit_cluster_aux(BDRVVVFATState* s,commit_t* commit)
+ /* adjust all references to mappings */
+ adjust_mapping_indices(s, mapping_index, -1);
+
+ if (s->current_mapping && first_mapping != (mapping_t*)s->mapping.pointer)
+ s->current_mapping = array_get(&(s->mapping),
+ s->current_mapping - first_mapping);
+
+ return 0;
+}
+
+static void adjust_dirindices(BDRVVVFATState* s, int offset, int adjust)
{
- int result=write_cluster(s,commit->cluster_num,commit->buf);
+ int i;
+ for (i = 0; i < s->mapping.next; i++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+ if (mapping->dir_index >= offset)
+ mapping->dir_index += adjust;
+ if ((mapping->mode & MODE_DIRECTORY) &&
+ mapping->info.dir.first_dir_index >= offset)
+ mapping->info.dir.first_dir_index += adjust;
+ }
+}
+
+static direntry_t* insert_direntries(BDRVVVFATState* s,
+ int dir_index, int count)
+{
+ /*
+ * make room in s->directory,
+ * adjust_dirindices
+ */
+ direntry_t* result = array_insert(&(s->directory), dir_index, count);
+ if (result == NULL)
+ return NULL;
+ adjust_dirindices(s, dir_index, count);
return result;
}
+static int remove_direntries(BDRVVVFATState* s, int dir_index, int count)
+{
+ int ret = array_remove_slice(&(s->directory), dir_index, count);
+ if (ret)
+ return ret;
+ adjust_dirindices(s, dir_index, -count);
+ return 0;
+}
-static int commit_cluster(BDRVVVFATState* s,uint32_t cluster_num)
+/*
+ * Adapt the mappings of the cluster chain starting at first cluster
+ * (i.e. if a file starts at first_cluster, the chain is followed according
+ * to the modified fat, and the corresponding entries in s->mapping are
+ * adjusted)
+ */
+static int commit_mappings(BDRVVVFATState* s,
+ uint32_t first_cluster, int dir_index)
{
- commit_t* commit;
+ mapping_t* mapping = find_mapping_for_cluster(s, first_cluster);
+ direntry_t* direntry = array_get(&(s->directory), dir_index);
+ uint32_t cluster = first_cluster;
+
+ vvfat_close_current_file(s);
+
+ assert(mapping);
+ assert(mapping->begin == first_cluster);
+ mapping->first_mapping_index = -1;
+ mapping->dir_index = dir_index;
+ mapping->mode = (dir_index <= 0 || is_directory(direntry)) ?
+ MODE_DIRECTORY : MODE_NORMAL;
+
+ while (!fat_eof(s, cluster)) {
+ uint32_t c, c1;
+
+ for (c = cluster, c1 = modified_fat_get(s, c); c + 1 == c1;
+ c = c1, c1 = modified_fat_get(s, c1));
+
+ c++;
+ if (c > mapping->end) {
+ int index = array_index(&(s->mapping), mapping);
+ int i, max_i = s->mapping.next - index;
+ for (i = 1; i < max_i && mapping[i].begin < c; i++);
+ while (--i > 0)
+ remove_mapping(s, index + 1);
+ }
+ assert(mapping == array_get(&(s->mapping), s->mapping.next - 1)
+ || mapping[1].begin >= c);
+ mapping->end = c;
+
+ if (!fat_eof(s, c1)) {
+ int i = find_mapping_for_cluster_aux(s, c1, 0, s->mapping.next);
+ mapping_t* next_mapping = i >= s->mapping.next ? NULL :
+ array_get(&(s->mapping), i);
+
+ if (next_mapping == NULL || next_mapping->begin > c1) {
+ int i1 = array_index(&(s->mapping), mapping);
+
+ next_mapping = insert_mapping(s, c1, c1+1);
+
+ if (c1 < c)
+ i1++;
+ mapping = array_get(&(s->mapping), i1);
+ }
+
+ next_mapping->dir_index = mapping->dir_index;
+ next_mapping->first_mapping_index =
+ mapping->first_mapping_index < 0 ?
+ array_index(&(s->mapping), mapping) :
+ mapping->first_mapping_index;
+ next_mapping->path = mapping->path;
+ next_mapping->mode = mapping->mode;
+ next_mapping->read_only = mapping->read_only;
+ if (mapping->mode & MODE_DIRECTORY) {
+ next_mapping->info.dir.parent_mapping_index =
+ mapping->info.dir.parent_mapping_index;
+ next_mapping->info.dir.first_dir_index =
+ mapping->info.dir.first_dir_index +
+ 0x10 * s->sectors_per_cluster *
+ (mapping->end - mapping->begin);
+ } else
+ next_mapping->info.file.offset = mapping->info.file.offset +
+ mapping->end - mapping->begin;
+
+ mapping = next_mapping;
+ }
+
+ cluster = c1;
+ }
- /* commit the sectors of this cluster */
- commit=get_commit_for_cluster(s,cluster_num);
- if(commit)
- return commit_cluster_aux(s,commit);
return 0;
}
-/* this function checks the consistency for the direntry which belongs to
- * the mapping. if everything is found consistent, the data is committed.
- * this returns 0 if no error occurred (even if inconsistencies were found) */
-static inline int commit_data_if_consistent(BDRVVVFATState* s,mapping_t*
mapping,write_action_t action)
+static int commit_direntries(BDRVVVFATState* s,
+ int dir_index, int parent_mapping_index)
{
- direntry_t* direntry;
-
- if(!mapping)
- return 0;
+ direntry_t* direntry = array_get(&(s->directory), dir_index);
+ uint32_t first_cluster = dir_index == 0 ? 0 : begin_of_direntry(direntry);
+ mapping_t* mapping = find_mapping_for_cluster(s, first_cluster);
- //fprintf(stderr,"7\n");
-#define d(x) fprintf(stderr,#x "\n")
- direntry=get_direntry_for_mapping(s,mapping);
+ int factor = 0x10 * s->sectors_per_cluster;
+ int old_cluster_count, new_cluster_count;
+ int current_dir_index = mapping->info.dir.first_dir_index;
+ int first_dir_index = current_dir_index;
+ int ret, i;
+ uint32_t c;
- //d(8);
+DLOG(fprintf(stderr, "commit_direntries for %s, parent_mapping_index %d\n",
mapping->path, parent_mapping_index));
- assert(action==WRITE_FAT || action==WRITE_DIRENTRY || action==WRITE_DATA);
+ assert(direntry);
+ assert(mapping);
+ assert(mapping->begin == first_cluster);
+ assert(mapping->info.dir.first_dir_index < s->directory.next);
+ assert(mapping->mode & MODE_DIRECTORY);
+ assert(dir_index == 0 || is_directory(direntry));
- //d(9);
- //fprintf(stderr,"mapping: 0x%x s=0x%x\n",(uint32_t)mapping,(uint32_t)s);
- /*fprintf(stderr,"commit? file=%s, action=%s\n",
-
mapping->filename,action==WRITE_FAT?"fat":action==WRITE_DIRENTRY?"direntry":"data");*/
+ mapping->info.dir.parent_mapping_index = parent_mapping_index;
- //d(10);
- if(s->action[2]==WRITE_UNDEFINED) {
- int i;
- for(i=2;i>0 && s->action[i-1]==WRITE_UNDEFINED;i--);
- if(i>0 && action!=s->action[i-1])
- s->action[i]=action;
- assert(i<2 || s->action[0]!=s->action[2]);
+ if (first_cluster == 0) {
+ old_cluster_count = new_cluster_count =
+ s->last_cluster_of_root_directory;
+ } else {
+ for (old_cluster_count = 0, c = first_cluster; !fat_eof(s, c);
+ c = fat_get(s, c))
+ old_cluster_count++;
+
+ for (new_cluster_count = 0, c = first_cluster; !fat_eof(s, c);
+ c = modified_fat_get(s, c))
+ new_cluster_count++;
}
- //d(11);
-
- if(mapping_is_consistent(s,mapping)==0) {
- uint32_t cluster_num=begin_of_direntry(direntry);
- off_t remaining_bytes=le32_to_cpu(direntry->size);
- //fprintf(stderr,"the data for %s was found
consistent\n",mapping->filename);
- while(remaining_bytes>0) {
- commit_t* commit=get_commit_for_cluster(s,cluster_num);
- if(!commit)
- continue;
-
- //fprintf(stderr,"commit_cluster %d (%d), remaining:
%d\n",cluster_num,s->max_fat_value-15,(int)remaining_bytes);
- assert(cluster_num>1);
- assert(cluster_num<s->max_fat_value-15);
- if(commit_cluster(s,cluster_num)) {
- fprintf(stderr,"error committing cluster %d\n",cluster_num);
- return -1;
- }
- cluster_num=fat_get(s,cluster_num);
- remaining_bytes-=s->cluster_size;
- /* TODO: if(action==s->action[2]) {
- commit_t* commit=get_commit_for_cluster(s,cluster_num);
- commit_remove(s,commit);
- } */
+
+ if (new_cluster_count > old_cluster_count) {
+ if (insert_direntries(s,
+ current_dir_index + factor * old_cluster_count,
+ factor * (new_cluster_count - old_cluster_count)) == NULL)
+ return -1;
+ } else if (new_cluster_count < old_cluster_count)
+ remove_direntries(s,
+ current_dir_index + factor * new_cluster_count,
+ factor * (old_cluster_count - new_cluster_count));
+
+ for (c = first_cluster; !fat_eof(s, c); c = modified_fat_get(s, c)) {
+ void* direntry = array_get(&(s->directory), current_dir_index);
+ int ret = vvfat_read(s->bs, cluster2sector(s, c), direntry,
+ s->sectors_per_cluster);
+ if (ret)
+ return ret;
+ assert(!strncmp(s->directory.pointer, "QEMU", 4));
+ current_dir_index += factor;
+ }
+
+ ret = commit_mappings(s, first_cluster, dir_index);
+ if (ret)
+ return ret;
+
+ /* recurse */
+ for (i = 0; i < factor * new_cluster_count; i++) {
+ direntry = array_get(&(s->directory), first_dir_index + i);
+ if (is_directory(direntry) && !is_dot(direntry)) {
+ mapping = find_mapping_for_cluster(s, first_cluster);
+ assert(mapping->mode & MODE_DIRECTORY);
+ ret = commit_direntries(s, first_dir_index + i,
+ array_index(&(s->mapping), mapping));
+ if (ret)
+ return ret;
}
}
- //print_mappings(s);
- //fprintf(stderr,"finish vvfat_write\n");
+
return 0;
}
-static int vvfat_write(BlockDriverState *bs, int64_t sector_num,
- const uint8_t *buf, int nb_sectors)
+/* commit one file (adjust contents, adjust mapping),
+ return first_mapping_index */
+static int commit_one_file(BDRVVVFATState* s,
+ int dir_index, uint32_t offset)
+{
+ direntry_t* direntry = array_get(&(s->directory), dir_index);
+ uint32_t c = begin_of_direntry(direntry);
+ uint32_t first_cluster = c;
+ mapping_t* mapping = find_mapping_for_cluster(s, c);
+ uint32_t size = filesize_of_direntry(direntry);
+ char* cluster = malloc(s->cluster_size);
+ uint32_t i;
+ int fd = 0;
+
+ assert(offset < size);
+ assert((offset % s->cluster_size) == 0);
+
+ for (i = s->cluster_size; i < offset; i += s->cluster_size)
+ c = modified_fat_get(s, c);
+
+ fd = open(mapping->path, O_RDWR | O_CREAT, 0666);
+ if (fd < 0) {
+ fprintf(stderr, "Could not open %s... (%s, %d)\n", mapping->path,
+ strerror(errno), errno);
+ return fd;
+ }
+ if (offset > 0)
+ if (lseek(fd, offset, SEEK_SET) != offset)
+ return -3;
+
+ while (offset < size) {
+ uint32_t c1;
+ int rest_size = (size - offset > s->cluster_size ?
+ s->cluster_size : size - offset);
+ int ret;
+
+ c1 = modified_fat_get(s, c);
+
+ assert((size - offset == 0 && fat_eof(s, c)) ||
+ (size > offset && c >=2 && !fat_eof(s, c)));
+ assert(size >= 0);
+
+ ret = vvfat_read(s->bs, cluster2sector(s, c),
+ cluster, (rest_size + 0x1ff) / 0x200);
+
+ if (ret < 0)
+ return ret;
+
+ if (write(fd, cluster, rest_size) < 0)
+ return -2;
+
+ offset += rest_size;
+ c = c1;
+ }
+
+ ftruncate(fd, size);
+ close(fd);
+
+ return commit_mappings(s, first_cluster, dir_index);
+}
+
+#ifdef DEBUG
+/* test, if all mappings point to valid direntries */
+static void check1(BDRVVVFATState* s)
{
- BDRVVVFATState *s = bs->opaque;
int i;
+ for (i = 0; i < s->mapping.next; i++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+ if (mapping->mode & MODE_DELETED) {
+ fprintf(stderr, "deleted\n");
+ continue;
+ }
+ assert(mapping->dir_index >= 0);
+ assert(mapping->dir_index < s->directory.next);
+ direntry_t* direntry = array_get(&(s->directory), mapping->dir_index);
+ assert(mapping->begin == begin_of_direntry(direntry) ||
mapping->first_mapping_index >= 0);
+ if (mapping->mode & MODE_DIRECTORY) {
+ assert(mapping->info.dir.first_dir_index + 0x10 *
s->sectors_per_cluster * (mapping->end - mapping->begin) <= s->directory.next);
+ assert((mapping->info.dir.first_dir_index % (0x10 *
s->sectors_per_cluster)) == 0);
+ }
+ }
+}
- /* fprintf(stderr,"vvfat_write %d+%d (%s)\n",(int)sector_num,nb_sectors,
- (sector_num>=s->faked_sectors?"data":
-
(sector_num>=s->first_sectors_number+2*s->sectors_per_fat?"directory":
-
(sector_num>=s->first_sectors_number+s->sectors_per_fat?"fat 2":
- (sector_num>=s->first_sectors_number?"fat 1":"boot
sector"))))); */
+/* test, if all direntries have mappings */
+static void check2(BDRVVVFATState* s)
+{
+ int i;
+ int first_mapping = -1;
- for(i=0;i<nb_sectors;i++,sector_num++,buf+=0x200) {
- print_changed_sector(bs,sector_num,buf);
+ for (i = 0; i < s->directory.next; i++) {
+ direntry_t* direntry = array_get(&(s->directory), i);
- if(sector_num<s->first_sectors_number) {
- /* change the bootsector or partition table? no! */
- return -1;
- } else if(sector_num<s->first_sectors_number+s->sectors_per_fat) {
- /* FAT 1 */
- int fat_entries_per_cluster=s->cluster_size*8/s->fat_type;
- int
first_cluster=(sector_num-s->first_sectors_number)*fat_entries_per_cluster,i;
- mapping_t* mapping=0;
-
- /* write back */
- memcpy(s->fat.pointer+0x200*(sector_num-s->first_sectors_number),
- buf,0x200);
-
- /* for each changed FAT entry, */
- for(i=0;i<fat_entries_per_cluster;i++) {
- int new_value;
-
- /* TODO: MODE_DIRENTRY */
-
if(first_cluster+i<s->sectors_for_directory/s->sectors_per_cluster)
- continue;
+ if (is_short_name(direntry) && begin_of_direntry(direntry)) {
+ mapping_t* mapping = find_mapping_for_cluster(s,
begin_of_direntry(direntry));
+ assert(mapping);
+ assert(mapping->dir_index == i || is_dot(direntry));
+ assert(mapping->begin == begin_of_direntry(direntry) ||
is_dot(direntry));
+ }
- new_value=fat_get(s,first_cluster+i);
+ if ((i % (0x10 * s->sectors_per_cluster)) == 0) {
+ /* cluster start */
+ int j, count = 0;
- /* check the current fat entry */
- if(new_value<2 || (new_value>=s->max_fat_value-0xf &&
!fat_eof(s,new_value))) {
- /* free, reserved or bad cluster */
- mapping=find_mapping_for_cluster(s,first_cluster+i);
- //assert(!mapping || mapping->mode==MODE_DELETED);
- if(mapping && mapping->mode==MODE_DELETED &&
- first_cluster+i+1==mapping->end)
-
array_remove(&(s->mapping),mapping-(mapping_t*)s->mapping.pointer);
- mapping=0;
+ for (j = 0; j < s->mapping.next; j++) {
+ mapping_t* mapping = array_get(&(s->mapping), j);
+ if (mapping->mode & MODE_DELETED)
continue;
+ if (mapping->mode & MODE_DIRECTORY) {
+ if (mapping->info.dir.first_dir_index <= i &&
mapping->info.dir.first_dir_index + 0x10 * s->sectors_per_cluster > i) {
+ assert(++count == 1);
+ if (mapping->first_mapping_index == -1)
+ first_mapping = array_index(&(s->mapping), mapping);
+ else
+ assert(first_mapping ==
mapping->first_mapping_index);
+ if (mapping->info.dir.parent_mapping_index < 0)
+ assert(j == 0);
+ else {
+ mapping_t* parent = array_get(&(s->mapping),
mapping->info.dir.parent_mapping_index);
+ assert(parent->mode & MODE_DIRECTORY);
+ assert(parent->info.dir.first_dir_index <
mapping->info.dir.first_dir_index);
+ }
+ }
}
+ }
+ if (count == 0)
+ first_mapping = -1;
+ }
+ }
+}
+#endif
- /* get the mapping for the current entry */
- if(!mapping || mapping->begin>new_value ||
mapping->end<=new_value) {
- mapping=find_mapping_for_cluster(s,first_cluster+i);
- }
+static int handle_renames_and_mkdirs(BDRVVVFATState* s)
+{
+ int i;
- print_mappings(s);
- fprintf(stderr,"fat_get(%d)=%d\n",first_cluster+i,new_value);
- /* TODO: what if there's no mapping? this is valid. */
- /* TODO: refactor the rest of this clause so it can be called
when the direntry changes, too */
- assert(mapping);
-
- if(new_value>1 && new_value<s->max_fat_value-0xf) {
- /* the cluster new_value points to is valid */
-
- if(first_cluster+i+1==new_value) {
- /* consecutive cluster */
- if(mapping->end<=new_value)
- mapping->end=new_value+1;
- } else {
- mapping_t* next_mapping;
-
- /* the current mapping ends here */
- mapping->end=first_cluster+i+1;
-
- /* the next mapping */
- next_mapping=find_mapping_for_cluster(s,new_value);
- if(next_mapping) {
- assert(mapping!=next_mapping);
- /* assert next mapping's filename is the same */
- assert(next_mapping->filename==mapping->filename);
- assert(next_mapping->dir_index==mapping->dir_index);
- /* assert next mapping is MODIFIED or UNDEFINED */
- assert(next_mapping->mode==MODE_MODIFIED ||
next_mapping->mode==MODE_UNDEFINED);
- } else {
- int
index=find_mapping_for_cluster_aux(s,new_value,0,s->mapping.next);
- next_mapping=array_insert(&(s->mapping),index,1);
- next_mapping->filename=mapping->filename;
- next_mapping->dir_index=mapping->dir_index;
- next_mapping->mode=MODE_MODIFIED;
- next_mapping->begin=0;
- }
- /* adjust offset of next mapping */
-
next_mapping->offset=mapping->offset+mapping->end-mapping->begin;
- /* set begin and possible end */
- if(next_mapping->begin!=new_value) {
- next_mapping->begin=new_value;
- next_mapping->end=new_value+1;
+#ifdef DEBUG
+ fprintf(stderr, "handle_renames\n");
+ for (i = 0; i < s->commits.next; i++) {
+ commit_t* commit = array_get(&(s->commits), i);
+ fprintf(stderr, "%d, %s (%d, %d)\n", i, commit->path ? commit->path :
"(null)", commit->param.rename.cluster, commit->action);
+ }
+#endif
+
+ for (i = 0; i < s->commits.next;) {
+ commit_t* commit = array_get(&(s->commits), i);
+ if (commit->action == ACTION_RENAME) {
+ mapping_t* mapping = find_mapping_for_cluster(s,
+ commit->param.rename.cluster);
+ char* old_path = mapping->path;
+
+ assert(commit->path);
+ mapping->path = commit->path;
+ if (rename(old_path, mapping->path))
+ return -2;
+
+ if (mapping->mode & MODE_DIRECTORY) {
+ int l1 = strlen(mapping->path);
+ int l2 = strlen(old_path);
+ int diff = l1 - l2;
+ direntry_t* direntry = array_get(&(s->directory),
+ mapping->info.dir.first_dir_index);
+ uint32_t c = mapping->begin;
+ int i;
+
+ /* recurse */
+ while (!fat_eof(s, c)) {
+ do {
+ direntry_t* d = direntry + i;
+
+ if (is_file(d) || (is_directory(d) && !is_dot(d))) {
+ mapping_t* m = find_mapping_for_cluster(s,
+ begin_of_direntry(d));
+ int l = strlen(m->path);
+ char* new_path = malloc(l + diff + 1);
+
+ assert(!strncmp(m->path, mapping->path, l2));
+
+ strcpy(new_path, mapping->path);
+ strcpy(new_path + l1, m->path + l2);
+
+ schedule_rename(s, m->begin, new_path);
}
- if(commit_data_if_consistent(s,mapping,WRITE_FAT))
- return -4;
- mapping=0;
- }
- } else if(fat_eof(s,new_value)) {
- /* the last cluster of the file */
- mapping->end=first_cluster+i+1;
- if(commit_data_if_consistent(s,mapping,WRITE_FAT))
- return -4;
- mapping=0;
+ i++;
+ } while((i % (0x10 * s->sectors_per_cluster)) != 0);
+ c = fat_get(s, c);
}
}
- } else if(sector_num<s->first_sectors_number+2*s->sectors_per_fat) {
- /* FAT 2: check if it is the same as FAT 1 */
-
if(memcmp(array_get(&(s->fat),sector_num-s->first_sectors_number),buf,0x200))
- return -1; /* mismatch */
- } else if(sector_num<s->faked_sectors) {
- /* direntry */
- /* - if they are in a directory, check if the entry has changed.
- * if yes, look what has changed (different strategies for name,
- * begin & size).
- *
- * if it is new (old entry is only 0's or has E5 at the start),
- * create it, and also create mapping, but in a special mode
- * "undefined", because we cannot know which clusters belong
- * to it yet.
- *
- * if it is zeroed, or has E5 at the start, look if has just
- * moved. If yes, copy the entry to the new position. If no,
- * delete the file.
- */
- mapping_t*
dir_mapping=find_mapping_for_cluster(s,sector2cluster(s,sector_num));
- direntry_t
*original=array_get(&(s->directory),sector_num-s->first_sectors_number-2*s->sectors_per_fat);
- direntry_t *new_=(direntry_t*)buf;
- int
first_dir_index=(sector_num-s->first_sectors_number-2*s->sectors_per_fat)*0x200/0x20;
- int j;
-#if 0
- fprintf(stderr,"direntry: consistency check\n");
+ free(old_path);
+ array_remove(&(s->commits), i);
+ continue;
+ } else if (commit->action == ACTION_MKDIR) {
+ mapping_t* mapping;
+ int j, parent_path_len;
+
+ if (mkdir(commit->path, 0755))
+ return -5;
+
+ mapping = insert_mapping(s, commit->param.mkdir.cluster,
+ commit->param.mkdir.cluster + 1);
+ if (mapping == NULL)
+ return -6;
+
+ mapping->mode = MODE_DIRECTORY;
+ mapping->read_only = 0;
+ mapping->path = commit->path;
+ j = s->directory.next;
+ assert(j);
+ insert_direntries(s, s->directory.next,
+ 0x10 * s->sectors_per_cluster);
+ mapping->info.dir.first_dir_index = j;
+
+ parent_path_len = strlen(commit->path)
+ - strlen(get_basename(commit->path)) - 1;
+ for (j = 0; j < s->mapping.next; j++) {
+ mapping_t* m = array_get(&(s->mapping), j);
+ if (m->first_mapping_index < 0 && m != mapping &&
+ !strncmp(m->path, mapping->path, parent_path_len) &&
+ strlen(m->path) == parent_path_len)
+ break;
+ }
+ assert(j < s->mapping.next);
+ mapping->info.dir.parent_mapping_index = j;
+
+ array_remove(&(s->commits), i);
+ continue;
+ }
+
+ i++;
+ }
+ return 0;
+}
+
+/*
+ * TODO: make sure that the short name is not matching *another* file
+ */
+static int handle_commits(BDRVVVFATState* s)
+{
+ int i, fail = 0;
- if(s->commit.next==0) {
- consistency_check1(s);
- consistency_check2(s);
- consistency_check3(s);
+ vvfat_close_current_file(s);
+
+ for (i = 0; !fail && i < s->commits.next; i++) {
+ commit_t* commit = array_get(&(s->commits), i);
+ switch(commit->action) {
+ case ACTION_RENAME: case ACTION_MKDIR:
+ assert(0);
+ fail = -2;
+ break;
+ case ACTION_WRITEOUT: {
+ direntry_t* entry = array_get(&(s->directory),
+ commit->param.writeout.dir_index);
+ uint32_t begin = begin_of_direntry(entry);
+ mapping_t* mapping = find_mapping_for_cluster(s, begin);
+
+ assert(mapping);
+ assert(mapping->begin == begin);
+ assert(commit->path == NULL);
+
+ if (commit_one_file(s, commit->param.writeout.dir_index,
+ commit->param.writeout.modified_offset))
+ fail = -3;
+
+ break;
+ }
+ case ACTION_NEW_FILE: {
+ int begin = commit->param.new_file.first_cluster;
+ mapping_t* mapping = find_mapping_for_cluster(s, begin);
+ direntry_t* entry;
+ int i;
+
+ /* find direntry */
+ for (i = 0; i < s->directory.next; i++) {
+ entry = array_get(&(s->directory), i);
+ if (is_file(entry) && begin_of_direntry(entry) == begin)
+ break;
}
-#endif
- assert(sizeof(direntry_t)==0x20);
+ if (i >= s->directory.next) {
+ fail = -6;
+ continue;
+ }
- for(j=0;j<0x200/0x20;j++) {
- //fprintf(stderr,"compare direntry %d:
0x%x,0x%x\n",j,(uint32_t)original+j,(uint32_t)new_+j);
- if(memcmp(original+j,new_+j,sizeof(direntry_t))) {
- //fprintf(stderr,"different\n");
- /* TODO: in create_short_filename, 0xe5->0x05 is not yet
handled! */
- if(direntry_is_free(original+j)) {
- mapping_t* mapping;
- char buffer[4096];
- int fd,i;
-
- if(new_[j].attributes==0xf)
- continue; /* long entry */
-
- print_mappings(s);
- //fprintf(stderr,"sector: %d cluster:
%d\n",(int)sector_num,(int)sector2cluster(s,sector_num));
-
- /* construct absolute path */
- strncpy(buffer,dir_mapping->filename,4096);
- i=strlen(buffer);
- if(i+2>=4096)
- return -1;
- buffer[i]='/';
- if(long2unix_name(buffer+i+1,4096-i-1,new_+j))
- return -2;
+ /* make sure there exists an initial mapping */
+ if (mapping && mapping->begin != begin) {
+ mapping->end = begin;
+ mapping = NULL;
+ }
+ if (mapping == NULL) {
+ mapping = insert_mapping(s, begin, begin+1);
+ }
+ /* most members will be fixed in commit_mappings() */
+ assert(commit->path);
+ mapping->path = commit->path;
+ mapping->read_only = 0;
+ mapping->mode = MODE_NORMAL;
+ mapping->info.file.offset = 0;
- /* new file/directory */
- if(new_[j].attributes&0x10) {
-#ifdef _WIN32
-#define SEVENFIVEFIVE
-#else
-#define SEVENFIVEFIVE ,0755
-#endif
- if(mkdir(buffer SEVENFIVEFIVE))
- return -3;
- /* TODO: map direntry.begin as directory, together
with new array_t direntries */
- assert(0);
- } else {
- fd=open(buffer,O_CREAT|O_EXCL,0644);
- if(!fd)
- return -3;
- close(fd);
- }
+ if (commit_one_file(s, i, 0))
+ fail = -7;
+
+ break;
+ }
+ default:
+ assert(0);
+ }
+ }
+ if (i > 0 && array_remove_slice(&(s->commits), 0, i))
+ return -1;
+ return fail;
+}
+
+static int handle_deletes(BDRVVVFATState* s)
+{
+ int i, deferred = 1, deleted = 1;
- /* create mapping */
-
i=find_mapping_for_cluster_aux(s,begin_of_direntry(new_+j),0,s->mapping.next);
- mapping=array_insert(&(s->mapping),i,1);
- mapping->filename=strdup(buffer);
- mapping->offset=0;
- /* back pointer to direntry */
- mapping->dir_index=first_dir_index+j;
- /* set mode to modified */
- mapping->mode=MODE_MODIFIED;
- /* set begin to direntry.begin */
- mapping->begin=begin_of_direntry(new_+j);
- /* set end to begin+1 */
- mapping->end=mapping->begin+1;
- /* commit file contents */
- if(commit_data_if_consistent(s,mapping,WRITE_DIRENTRY))
{
- fprintf(stderr,"error committing file contents for
new file %s!\n",buffer);
- return -4;
+ /* delete files corresponding to mappings marked as deleted */
+ /* handle DELETEs and unused mappings (modified_fat_get(s, mapping->begin)
== 0) */
+ while (deferred && deleted) {
+ deferred = 0;
+ deleted = 0;
+
+ for (i = 1; i < s->mapping.next; i++) {
+ mapping_t* mapping = array_get(&(s->mapping), i);
+ if (mapping->mode & MODE_DELETED) {
+ direntry_t* entry = array_get(&(s->directory),
+ mapping->dir_index);
+
+ if (is_free(entry)) {
+ /* remove file/directory */
+ if (mapping->mode & MODE_DIRECTORY) {
+ int j, next_dir_index = s->directory.next,
+ first_dir_index = mapping->info.dir.first_dir_index;
+
+ if (rmdir(mapping->path) < 0) {
+ if (errno == ENOTEMPTY) {
+ deferred++;
+ continue;
+ } else
+ return -5;
}
- } else if(direntry_is_free(new_+j)) {
- assert(0);
- /* TODO: delete file */
- /* TODO: write direntry */
- /* TODO: modify mapping: set mode=deleted */
- } else {
- /* modified file */
- mapping_t* mapping=0;
- /* if direntry.begin has changed,
- * set mode to modified,
- * adapt begin,
- * adapt end */
- /* TODO: handle rename */
- assert(!memcmp(new_[j].name,original[j].name,11));
- //fprintf(stderr,"1\n");
- if(new_[j].begin!=original[j].begin ||
new_[j].size/s->cluster_size!=original[j].size/s->cluster_size) {
- //fprintf(stderr,"2\n");
- mapping = find_mapping_for_direntry(s,original+j);
- //fprintf(stderr,"3\n");
- if(!mapping) /* this should never happen! */
- return -2;
- mapping_modify_from_direntry(s,mapping,new_+j);
- //fprintf(stderr,"4\n");
-
if(commit_data_if_consistent(s,mapping,WRITE_DIRENTRY)) {
- fprintf(stderr,"big error\n");
- return -4;
- }
+
+ for (j = 1; j < s->mapping.next; j++) {
+ mapping_t* m = array_get(&(s->mapping), j);
+ if (m->mode & MODE_DIRECTORY &&
+ m->info.dir.first_dir_index >
+ first_dir_index &&
+ m->info.dir.first_dir_index <
+ next_dir_index)
+ next_dir_index =
+ m->info.dir.first_dir_index;
}
- /* TODO: handle modified times and other attributes */
+ remove_direntries(s, first_dir_index,
+ next_dir_index - first_dir_index);
- //fprintf(stderr,"5: mapping=0x%x, s=0x%x,
s->mapping.pointer=0x%x\n",(uint32_t)mapping,(uint32_t)s,(uint32_t)s->mapping.pointer);
- //fprintf(stderr,"6\n");
+ deleted++;
}
+ } else {
+ if (unlink(mapping->path))
+ return -4;
+ deleted++;
}
- }
- /* write back direntries */
- memcpy(original,new_,0x200);
- } else {
- /* data */
- off_t
sector=sector_num-s->first_sectors_number-2*s->sectors_per_fat;
- off_t cluster=sector/s->sectors_per_cluster;
- mapping_t* mapping=find_mapping_for_cluster(s,cluster);
- if(mapping && mapping->mode==MODE_DELETED)
- return -3; /* this is an error: no writes to these clusters
before committed */
- {
- /* as of yet, undefined: put into commits */
- commit_t* commit=create_or_get_commit_for_sector(s,sector_num);
-
- if(!commit)
- return -1; /* out of memory */
-
memcpy(commit->buf+0x200*sector_offset_in_cluster(s,sector_num),buf,0x200);
-
- //fprintf(stderr,"mapping: 0x%x\n",(uint32_t)mapping);
- if(commit_data_if_consistent(s,mapping,WRITE_DATA))
- return -4;
+ DLOG(fprintf(stderr, "DELETE (%d)\n", i);
print_mapping(mapping); print_direntry(entry));
+ remove_mapping(s, i);
}
}
}
+
+ return 0;
+}
+
+/*
+ * synchronize mapping with new state:
+ *
+ * - copy FAT (with bdrv_read)
+ * - mark all filenames corresponding to mappings as deleted
+ * - recurse direntries from root (using bs->bdrv_read)
+ * - delete files corresponding to mappings marked as deleted
+ */
+static int do_commit(BDRVVVFATState* s)
+{
+ int ret = 0;
+
+ /* the real meat are the commits. Nothing to do? Move along! */
+ if (s->commits.next == 0)
+ return 0;
+
+ vvfat_close_current_file(s);
+
+ ret = handle_renames_and_mkdirs(s);
+ if (ret) {
+ fprintf(stderr, "Error handling renames (%d)\n", ret);
+ assert(0);
+ return ret;
+ }
+
+ /* copy FAT (with bdrv_read) */
+ memcpy(s->fat.pointer, s->fat2, 0x200 * s->sectors_per_fat);
+
+ /* recurse direntries from root (using bs->bdrv_read) */
+ ret = commit_direntries(s, 0, -1);
+ if (ret) {
+ fprintf(stderr, "Fatal: error while committing (%d)\n", ret);
+ assert(0);
+ return ret;
+ }
+
+ ret = handle_commits(s);
+ if (ret) {
+ fprintf(stderr, "Error handling commits (%d)\n", ret);
+ assert(0);
+ return ret;
+ }
+
+ ret = handle_deletes(s);
+ if (ret) {
+ fprintf(stderr, "Error deleting\n");
+ assert(0);
+ return ret;
+ }
+
+ s->qcow->drv->bdrv_make_empty(s->qcow);
+
+ memset(s->used_clusters, 0, sector2cluster(s, s->sector_count));
+
+DLOG(checkpoint());
+ return 0;
+}
+
+static int try_commit(BDRVVVFATState* s)
+{
+ vvfat_close_current_file(s);
+DLOG(checkpoint());
+ if(!is_consistent(s))
+ return -1;
+ return do_commit(s);
+}
+
+static int vvfat_write(BlockDriverState *bs, int64_t sector_num,
+ const uint8_t *buf, int nb_sectors)
+{
+ BDRVVVFATState *s = bs->opaque;
+ int i, ret;
+
+DLOG(checkpoint());
+
+ vvfat_close_current_file(s);
+
+ /*
+ * Some sanity checks:
+ * - do not allow writing to the boot sector
+ * - do not allow to write non-ASCII filenames
+ */
+
+ if (sector_num < s->first_sectors_number)
+ return -1;
+
+ for (i = sector2cluster(s, sector_num);
+ i <= sector2cluster(s, sector_num + nb_sectors - 1);) {
+ mapping_t* mapping = find_mapping_for_cluster(s, i);
+ if (mapping) {
+ if (mapping->read_only) {
+ fprintf(stderr, "Tried to write to write-protected file %s\n",
+ mapping->path);
+ return -1;
+ }
+
+ if (mapping->mode & MODE_DIRECTORY) {
+ int begin = cluster2sector(s, i);
+ int end = begin + s->sectors_per_cluster, k;
+ int dir_index;
+ const direntry_t* direntries;
+ long_file_name lfn;
+
+ lfn_init(&lfn);
+
+ if (begin < sector_num)
+ begin = sector_num;
+ if (end > sector_num + nb_sectors)
+ end = sector_num + nb_sectors;
+ dir_index = mapping->dir_index +
+ 0x10 * (begin - mapping->begin * s->sectors_per_cluster);
+ direntries = (direntry_t*)(buf + 0x200 * (begin - sector_num));
+
+ for (k = 0; k < (end - begin) * 0x10; k++) {
+ /* do not allow non-ASCII filenames */
+ if (parse_long_name(&lfn, direntries + k) < 0) {
+ fprintf(stderr, "Warning: non-ASCII filename\n");
+ return -1;
+ }
+ /* no access to the direntry of a read-only file */
+ else if (is_short_name(direntries+k) &&
+ (direntries[k].attributes & 1)) {
+ if (memcmp(direntries + k,
+ array_get(&(s->directory), dir_index + k),
+ sizeof(direntry_t))) {
+ fprintf(stderr, "Warning: tried to write to
write-protected file\n");
+ return -1;
+ }
+ }
+ }
+ }
+ i = mapping->end;
+ } else
+ i++;
+ }
+
+ /*
+ * Use qcow backend. Commit later.
+ */
+DLOG(fprintf(stderr, "Write to qcow backend: %d + %d\n", (int)sector_num,
nb_sectors));
+ ret = s->qcow->drv->bdrv_write(s->qcow, sector_num, buf, nb_sectors);
+ if (ret < 0) {
+ fprintf(stderr, "Error writing to qcow backend\n");
+ return ret;
+ }
+
+ for (i = sector2cluster(s, sector_num);
+ i <= sector2cluster(s, sector_num + nb_sectors - 1); i++)
+ if (i >= 0)
+ s->used_clusters[i] |= USED_ALLOCATED;
+
+DLOG(checkpoint());
+ /* TODO: add timeout */
+ try_commit(s);
+
+DLOG(checkpoint());
+ return 0;
+}
+
+static int vvfat_is_allocated(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors, int* n)
+{
+ BDRVVVFATState* s = bs->opaque;
+ *n = s->sector_count - sector_num;
+ if (*n > nb_sectors)
+ *n = nb_sectors;
+ else if (*n < 0)
+ return 0;
+ return 1;
+}
+
+static int write_target_commit(BlockDriverState *bs, int64_t sector_num,
+ const uint8_t* buffer, int nb_sectors) {
+ BDRVVVFATState* s = bs->opaque;
+ return try_commit(s);
+}
+
+static void write_target_close(BlockDriverState *bs) {
+ BDRVVVFATState* s = bs->opaque;
+ bdrv_delete(s->qcow);
+ free(s->qcow_filename);
+}
+
+static BlockDriver vvfat_write_target = {
+ "vvfat_write_target", 0, NULL, NULL, NULL,
+ write_target_commit,
+ write_target_close,
+ NULL, NULL, NULL
+};
+
+static int enable_write_target(BDRVVVFATState *s)
+{
+ int size = sector2cluster(s, s->sector_count);
+ s->used_clusters = calloc(size, 1);
+
+ array_init(&(s->commits), sizeof(commit_t));
+
+ s->qcow_filename = malloc(1024);
+ strcpy(s->qcow_filename, "/tmp/vl.XXXXXX");
+ get_tmp_filename(s->qcow_filename, strlen(s->qcow_filename) + 1);
+ if (bdrv_create(&bdrv_qcow,
+ s->qcow_filename, s->sector_count, "fat:", 0) < 0)
+ return -1;
+ s->qcow = bdrv_new("");
+ if (s->qcow == NULL || bdrv_open(s->qcow, s->qcow_filename, 0) < 0)
+ return -1;
+
+#ifndef _WIN32
+ unlink(s->qcow_filename);
+#endif
+
+ s->bs->backing_hd = calloc(sizeof(BlockDriverState), 1);
+ s->bs->backing_hd->drv = &vvfat_write_target;
+ s->bs->backing_hd->opaque = s;
+
return 0;
}
@@ -1725,8 +2753,8 @@ static void vvfat_close(BlockDriverState
array_free(&(s->fat));
array_free(&(s->directory));
array_free(&(s->mapping));
- if(s->cluster)
- free(s->cluster);
+ if(s->cluster_buffer)
+ free(s->cluster_buffer);
}
BlockDriver bdrv_vvfat = {
@@ -1737,6 +2765,36 @@ BlockDriver bdrv_vvfat = {
vvfat_read,
vvfat_write,
vvfat_close,
+ NULL,
+ vvfat_is_allocated
};
+#ifdef DEBUG
+static void checkpoint() {
+ assert(((mapping_t*)array_get(&(vvv->mapping), 0))->end == 2);
+ check1(vvv);
+ check2(vvv);
+ assert(!vvv->current_mapping || vvv->current_fd ||
(vvv->current_mapping->mode & MODE_DIRECTORY));
+#if 0
+ if (((direntry_t*)vvv->directory.pointer)[1].attributes != 0xf)
+ fprintf(stderr, "Nonono!\n");
+ mapping_t* mapping;
+ direntry_t* direntry;
+ assert(vvv->mapping.size >= vvv->mapping.item_size * vvv->mapping.next);
+ assert(vvv->directory.size >= vvv->directory.item_size *
vvv->directory.next);
+ if (vvv->mapping.next<47)
+ return;
+ assert((mapping = array_get(&(vvv->mapping), 47)));
+ assert(mapping->dir_index < vvv->directory.next);
+ direntry = array_get(&(vvv->directory), mapping->dir_index);
+ assert(!memcmp(direntry->name, "USB H ", 11) || direntry->name[0]==0);
+#endif
+ return;
+ /* avoid compiler warnings: */
+ hexdump(NULL, 100);
+ remove_mapping(vvv, NULL);
+ print_mapping(NULL);
+ print_direntry(NULL);
+}
+#endif
diff --git a/block.c b/block.c
index efd96e6..6924cee 100644
--- a/block.c
+++ b/block.c
@@ -150,13 +150,19 @@ int bdrv_create(BlockDriver *drv,
}
#ifdef _WIN32
-static void get_tmp_filename(char *filename, int size)
+void get_tmp_filename(char *filename, int size)
{
+ char* p = strrchr(filename, '/');
+
+ if (p == NULL)
+ return;
+
/* XXX: find a better function */
- tmpnam(filename);
+ tmpnam(p);
+ *p = '/';
}
#else
-static void get_tmp_filename(char *filename, int size)
+void get_tmp_filename(char *filename, int size)
{
int fd;
/* XXX: race condition possible */
@@ -394,6 +400,10 @@ int bdrv_commit(BlockDriverState *bs)
i += n;
}
}
+
+ if (bs->drv->bdrv_make_empty)
+ return bs->drv->bdrv_make_empty(bs);
+
return 0;
}
diff --git a/block_int.h b/block_int.h
index 03744f7..e303816 100644
--- a/block_int.h
+++ b/block_int.h
@@ -39,6 +39,7 @@ struct BlockDriver {
int (*bdrv_is_allocated)(BlockDriverState *bs, int64_t sector_num,
int nb_sectors, int *pnum);
int (*bdrv_set_key)(BlockDriverState *bs, const char *key);
+ int (*bdrv_make_empty)(BlockDriverState *bs);
struct BlockDriver *next;
};
@@ -74,4 +75,6 @@ struct BlockDriverState {
BlockDriverState *next;
};
+void get_tmp_filename(char *filename, int size);
+
#endif /* BLOCK_INT_H */
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- [Qemu-devel] [PATCH] Major overhaul of block-vvfat,
Johannes Schindelin <=