[Emacs-diffs] Changes to emacs/src/callproc.c,v

[Miles Bader]

CVSROOT:        /cvsroot/emacs
Module name:    emacs
Changes by:     Miles Bader <miles>     07/08/29 05:28:10

Index: src/callproc.c
===================================================================
RCS file: /cvsroot/emacs/emacs/src/callproc.c,v
retrieving revision 1.223
retrieving revision 1.224
diff -u -b -r1.223 -r1.224
--- src/callproc.c      13 Aug 2007 13:41:10 -0000      1.223
+++ src/callproc.c      29 Aug 2007 05:27:51 -0000      1.224
@@ -84,6 +84,8 @@
 #include "syssignal.h"
 #include "systty.h"
 #include "blockinput.h"
+#include "frame.h"
+#include "termhooks.h"
 
 #ifdef MSDOS
 #include "msdos.h"
@@ -131,6 +133,7 @@
    this is exit code of synchronous subprocess.  */
 int synch_process_retcode;
 
+
 /* Clean up when exiting Fcall_process.
    On MSDOS, delete the temporary file on any kind of termination.
    On Unix, kill the process and any children on termination by signal.  */
@@ -1181,6 +1184,40 @@
 
 static int relocate_fd ();
 
+static char **
+add_env (char **env, char **new_env, char *string)
+{
+  char **ep;
+  int ok = 1;
+  if (string == NULL)
+    return new_env;
+
+  /* See if this string duplicates any string already in the env.
+     If so, don't put it in.
+     When an env var has multiple definitions,
+     we keep the definition that comes first in process-environment.  */
+  for (ep = env; ok && ep != new_env; ep++)
+    {
+      char *p = *ep, *q = string;
+      while (ok)
+        {
+          if (*q != *p)
+            break;
+          if (*q == 0)
+            /* The string is a lone variable name; keep it for now, we
+               will remove it later.  It is a placeholder for a
+               variable that is not to be included in the environment.  */
+            break;
+          if (*q == '=')
+            ok = 0;
+          p++, q++;
+        }
+    }
+  if (ok)
+    *new_env++ = string;
+  return new_env;
+}
+
 /* This is the last thing run in a newly forked inferior
    either synchronous or asynchronous.
    Copy descriptors IN, OUT and ERR as descriptors 0, 1 and 2.
@@ -1208,6 +1245,8 @@
 {
   char **env;
   char *pwd_var;
+  char *term_var;
+  char *display_var;
 #ifdef WINDOWSNT
   int cpid;
   HANDLE handles[3];
@@ -1282,57 +1321,101 @@
       temp[--i] = 0;
   }
 
-  /* Set `env' to a vector of the strings in Vprocess_environment.  */
+  /* Set `env' to a vector of the strings in the environment.  */
   {
     register Lisp_Object tem;
     register char **new_env;
+    char **p, **q;
     register int new_length;
+    Lisp_Object local = selected_frame; /* get_frame_param (XFRAME 
(Fframe_with_environment (selected_frame)), */
+/*                                          Qenvironment); */
+
+    Lisp_Object term;
+    Lisp_Object display;
 
     new_length = 0;
+
     for (tem = Vprocess_environment;
         CONSP (tem) && STRINGP (XCAR (tem));
         tem = XCDR (tem))
       new_length++;
 
+#if 0    
+    for (tem = local;
+        CONSP (tem) && STRINGP (XCAR (tem));
+        tem = XCDR (tem))
+      new_length++;
+#endif
+
+    /* Add TERM and DISPLAY from the frame local values. */
+    term = get_frame_param (XFRAME (local), Qterm_environment_variable);
+    if (! NILP (term))
+      new_length++;
+
+    display = get_frame_param (XFRAME (local), Qdisplay_environment_variable);
+    if (! NILP (display))
+      new_length++;
+
     /* new_length + 2 to include PWD and terminating 0.  */
     env = new_env = (char **) alloca ((new_length + 2) * sizeof (char *));
 
     /* If we have a PWD envvar, pass one down,
        but with corrected value.  */
-    if (getenv ("PWD"))
+    if (egetenv ("PWD"))
       *new_env++ = pwd_var;
 
-    /* Copy the Vprocess_environment strings into new_env.  */
+    if (! NILP (term))
+      {
+       int vlen = strlen ("TERM=") + strlen (SDATA (term)) + 1;
+       char *vdata = (char *) alloca (vlen);
+       strcpy (vdata, "TERM=");
+       strcat (vdata, SDATA (term));
+       new_env = add_env (env, new_env, vdata);
+      }
+
+    if (! NILP (display))
+      {
+       int vlen = strlen ("DISPLAY=") + strlen (SDATA (display)) + 1;
+       char *vdata = (char *) alloca (vlen);
+       strcpy (vdata, "DISPLAY=");
+       strcat (vdata, SDATA (display));
+       new_env = add_env (env, new_env, vdata);
+      }
+
+    /* Overrides.  */
     for (tem = Vprocess_environment;
         CONSP (tem) && STRINGP (XCAR (tem));
         tem = XCDR (tem))
       {
-       char **ep = env;
-       char *string = (char *) SDATA (XCAR (tem));
-       /* See if this string duplicates any string already in the env.
-          If so, don't put it in.
-          When an env var has multiple definitions,
-          we keep the definition that comes first in process-environment.  */
-       for (; ep != new_env; ep++)
-         {
-           char *p = *ep, *q = string;
-           while (1)
-             {
-               if (*q == 0)
-                 /* The string is malformed; might as well drop it.  */
-                 goto duplicate;
-               if (*q != *p)
-                 break;
-               if (*q == '=')
-                 goto duplicate;
-               p++, q++;
-             }
-         }
-       *new_env++ = string;
-      duplicate: ;
+       if ((strcmp (SDATA (XCAR (tem)), "TERM") != 0)
+           && (strcmp (SDATA (XCAR (tem)), "DISPLAY") != 0))
+         new_env = add_env (env, new_env, SDATA (XCAR (tem)));
       }
+
+  
+#if 0    
+    /* Local part of environment.  */
+    for (tem = local;
+         CONSP (tem) && STRINGP (XCAR (tem));
+         tem = XCDR (tem))
+      new_env = add_env (env, new_env, SDATA (XCAR (tem)));
+#endif
+    
     *new_env = 0;
+
+    /* Remove variable names without values.  */
+    p = q = env;
+    while (*p != 0)
+      {
+        while (*q != 0 && strchr (*q, '=') == NULL)
+          *q++;
+        *p = *q++;
+        if (*p != 0)
+          p++;
   }
+  }
+
+  
 #ifdef WINDOWSNT
   prepare_standard_handles (in, out, err, handles);
   set_process_dir (SDATA (current_dir));
@@ -1446,16 +1529,109 @@
 }
 
 static int
-getenv_internal (var, varlen, value, valuelen)
+getenv_internal (var, varlen, value, valuelen, frame)
      char *var;
      int varlen;
      char **value;
      int *valuelen;
+     Lisp_Object frame;
 {
   Lisp_Object scan;
+  Lisp_Object term;
+  Lisp_Object display;
+  
 
+  if (NILP (frame))
+    {
+      /* Try to find VAR in Vprocess_environment first.  */
+      for (scan = Vprocess_environment; CONSP (scan); scan = XCDR (scan))
+        {
+          Lisp_Object entry = XCAR (scan);
+          if (STRINGP (entry)
+              && SBYTES (entry) >= varlen
+#ifdef WINDOWSNT
+              /* NT environment variables are case insensitive.  */
+              && ! strnicmp (SDATA (entry), var, varlen)
+#else  /* not WINDOWSNT */
+              && ! bcmp (SDATA (entry), var, varlen)
+#endif /* not WINDOWSNT */
+              )
+            {
+              if (SBYTES (entry) > varlen && SREF (entry, varlen) == '=')
+                {
+                  *value = (char *) SDATA (entry) + (varlen + 1);
+                  *valuelen = SBYTES (entry) - (varlen + 1);
+                  return 1;
+                }
+              else if (SBYTES (entry) == varlen)
+                {
+                  /* Lone variable names in Vprocess_environment mean that
+                     variable should be removed from the environment. */
+                  return 0;
+                }
+            }
+        }
+      frame = selected_frame;
+    }
+
+  /* For TERM and DISPLAY first try to get the values from the frame. */
+  term = get_frame_param (XFRAME (frame), Qterm_environment_variable);
+  if (strcmp (var, "TERM") == 0)
+    if (! NILP (term))
+      {
+         *value    = (char *) SDATA (term);
+         *valuelen = SBYTES (term);
+         return 1;
+      }
+  display = get_frame_param (XFRAME (frame), Qdisplay_environment_variable);
+  if (strcmp (var, "DISPLAY") == 0)
+    if (! NILP (display))
+      {
+         *value    = (char *) SDATA (display);
+         *valuelen = SBYTES (display);
+         return 1;
+      }
+
+  {
+    /* Try to find VAR in Vprocess_environment.  */
   for (scan = Vprocess_environment; CONSP (scan); scan = XCDR (scan))
     {
+       Lisp_Object entry = XCAR (scan);
+       if (STRINGP (entry)
+           && SBYTES (entry) >= varlen
+#ifdef WINDOWSNT
+           /* NT environment variables are case insensitive.  */
+           && ! strnicmp (SDATA (entry), var, varlen)
+#else  /* not WINDOWSNT */
+           && ! bcmp (SDATA (entry), var, varlen)
+#endif /* not WINDOWSNT */
+           )
+         {
+           if (SBYTES (entry) > varlen && SREF (entry, varlen) == '=')
+             {
+               *value = (char *) SDATA (entry) + (varlen + 1);
+               *valuelen = SBYTES (entry) - (varlen + 1);
+               return 1;
+             }
+           else if (SBYTES (entry) == varlen)
+             {
+               /* Lone variable names in Vprocess_environment mean that
+                  variable should be removed from the environment. */
+               return 0;
+             }
+         }
+      }
+  }
+
+#if 0
+  /* Find the environment in which to search the variable. */
+  CHECK_FRAME (frame);
+  frame = Fframe_with_environment (frame);
+
+  for (scan = get_frame_param (XFRAME (frame), Qenvironment);
+       CONSP (scan);
+       scan = XCDR (scan))
+    {
       Lisp_Object entry;
 
       entry = XCAR (scan);
@@ -1475,30 +1651,38 @@
          return 1;
        }
     }
-
+#endif
   return 0;
 }
 
-DEFUN ("getenv-internal", Fgetenv_internal, Sgetenv_internal, 1, 1, 0,
-       doc: /* Return the value of environment variable VAR, as a string.
-VAR should be a string.  Value is nil if VAR is undefined in the environment.
-This function consults the variable `process-environment' for its value.  */)
-     (var)
-     Lisp_Object var;
+DEFUN ("getenv-internal", Fgetenv_internal, Sgetenv_internal, 1, 2, 0,
+       doc: /* Get the value of environment variable VARIABLE.
+VARIABLE should be a string.  Value is nil if VARIABLE is undefined in
+the environment.  Otherwise, value is a string.
+
+This function searches `process-environment' for VARIABLE.  If it is
+not found there, then it continues the search in the environment list
+of the selected frame.
+
+If optional parameter FRAME is non-nil, then this function will ignore
+`process-environment' and will simply look up the variable in that
+frame's environment.  */)
+     (variable, frame)
+     Lisp_Object variable, frame;
 {
   char *value;
   int valuelen;
 
-  CHECK_STRING (var);
-  if (getenv_internal (SDATA (var), SBYTES (var),
-                      &value, &valuelen))
+  CHECK_STRING (variable);
+  if (getenv_internal (SDATA (variable), SBYTES (variable),
+                      &value, &valuelen, frame))
     return make_string (value, valuelen);
   else
     return Qnil;
 }
 
-/* A version of getenv that consults process_environment, easily
-   callable from C.  */
+/* A version of getenv that consults the Lisp environment lists,
+   easily callable from C.  */
 char *
 egetenv (var)
      char *var;
@@ -1506,7 +1690,7 @@
   char *value;
   int valuelen;
 
-  if (getenv_internal (var, strlen (var), &value, &valuelen))
+  if (getenv_internal (var, strlen (var), &value, &valuelen, Qnil))
     return value;
   else
     return 0;
@@ -1646,17 +1830,19 @@
 }
 
 void
-set_process_environment ()
+set_initial_environment ()
 {
   register char **envp;
-
-  Vprocess_environment = Qnil;
+  Lisp_Object env = Vprocess_environment;
 #ifndef CANNOT_DUMP
   if (initialized)
 #endif
+    {
     for (envp = environ; *envp; envp++)
       Vprocess_environment = Fcons (build_string (*envp),
                                    Vprocess_environment);
+      store_frame_param (SELECTED_FRAME(), Qenvironment, Vprocess_environment);
+    }
 }
 
 void
@@ -1716,15 +1902,27 @@
   /* This variable is initialized in init_callproc.  */
 
   DEFVAR_LISP ("process-environment", &Vprocess_environment,
-              doc: /* List of environment variables for subprocesses to 
inherit.
+              doc: /* List of overridden environment variables for 
subprocesses to inherit.
 Each element should be a string of the form ENVVARNAME=VALUE.
+
+Entries in this list take precedence to those in the frame-local
+environments.  Therefore, let-binding `process-environment' is an easy
+way to temporarily change the value of an environment variable,
+irrespective of where it comes from.  To use `process-environment' to
+remove an environment variable, include only its name in the list,
+without "=VALUE".
+
+This variable is set to nil when Emacs starts.
+
 If multiple entries define the same variable, the first one always
 takes precedence.
-The environment which Emacs inherits is placed in this variable
-when Emacs starts.
+
 Non-ASCII characters are encoded according to the initial value of
-`locale-coding-system', i.e. the elements must normally be decoded for use.
+`locale-coding-system', i.e. the elements must normally be decoded for
+use.
+
 See `setenv' and `getenv'.  */);
+  Vprocess_environment = Qnil;
 
 #ifndef VMS
   defsubr (&Scall_process);