[PATCH] posixtm: avoid compiler warning in a better way

[Paul Eggert]

* lib/posixtm.c (IF_LINT): Remove.
(year, posix_time_parse):
Return true (not 0) if successful.  All callers changed.
(posix_time_parse): Simplify to pacify GCC without need for IF_LINT.
---
 ChangeLog     |  8 ++++++
 lib/posixtm.c | 80 ++++++++++++++++++++++++-----------------------------------
 2 files changed, 40 insertions(+), 48 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index f6f65c8..5fac19d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2014-12-09  Paul Eggert  <address@hidden>
+
+       posixtm: avoid compiler warning in a better way
+       * lib/posixtm.c (IF_LINT): Remove.
+       (year, posix_time_parse):
+       Return true (not 0) if successful.  All callers changed.
+       (posix_time_parse): Simplify to pacify GCC without need for IF_LINT.
+
 2014-12-08  KO Myung-Hun  <address@hidden>
 
        * lib/relocatable.c (relocate): Prepend $UNIXROOT to pathname if it is
diff --git a/lib/posixtm.c b/lib/posixtm.c
index 3023932..3e40f22 100644
--- a/lib/posixtm.c
+++ b/lib/posixtm.c
@@ -27,13 +27,6 @@
 #include <sys/types.h>
 #include <string.h>
 
-/* Use this to suppress gcc's "...may be used uninitialized" warnings. */
-#ifdef lint
-# define IF_LINT(Code) Code
-#else
-# define IF_LINT(Code) /* empty */
-#endif
-
 #if USE_UNLOCKED_IO
 # include "unlocked-io.h"
 #endif
@@ -64,7 +57,7 @@
 
 */
 
-static int
+static bool
 year (struct tm *tm, const int *digit_pair, size_t n, unsigned int syntax_bits)
 {
   switch (n)
@@ -77,14 +70,14 @@ year (struct tm *tm, const int *digit_pair, size_t n, 
unsigned int syntax_bits)
       if (digit_pair[0] <= 68)
         {
           if (syntax_bits & PDS_PRE_2000)
-            return 1;
+            return false;
           tm->tm_year += 100;
         }
       break;
 
     case 2:
       if (! (syntax_bits & PDS_CENTURY))
-        return 1;
+        return false;
       tm->tm_year = digit_pair[0] * 100 + digit_pair[1] - 1900;
       break;
 
@@ -97,7 +90,7 @@ year (struct tm *tm, const int *digit_pair, size_t n, 
unsigned int syntax_bits)
         time (&now);
         tmp = localtime (&now);
         if (! tmp)
-          return 1;
+          return false;
         tm->tm_year = tmp->tm_year;
       }
       break;
@@ -106,10 +99,10 @@ year (struct tm *tm, const int *digit_pair, size_t n, 
unsigned int syntax_bits)
       abort ();
     }
 
-  return 0;
+  return true;
 }
 
-static int
+static bool
 posix_time_parse (struct tm *tm, const char *s, unsigned int syntax_bits)
 {
   const char *dot = NULL;
@@ -118,27 +111,25 @@ posix_time_parse (struct tm *tm, const char *s, unsigned 
int syntax_bits)
   size_t i;
 
   size_t s_len = strlen (s);
-  size_t len = (((syntax_bits & PDS_SECONDS) && (dot = strchr (s, '.')))
-                ? (size_t) (dot - s)
-                : s_len);
-
-  if (len != 8 && len != 10 && len != 12)
-    return 1;
+  size_t len = s_len;
 
-  IF_LINT(if (len < 8) return 1;)
-
-  if (dot)
+  if (syntax_bits & PDS_SECONDS)
     {
-      if (!(syntax_bits & PDS_SECONDS))
-        return 1;
-
-      if (s_len - len != 3)
-        return 1;
+      dot = strchr (s, '.');
+      if (dot)
+        {
+          len = dot - s;
+          if (s_len - len != 3)
+            return false;
+        }
     }
 
+  if (! (8 <= len && len <= 12 && len % 2 == 0))
+    return false;
+
   for (i = 0; i < len; i++)
     if (!ISDIGIT (s[i]))
-      return 1;
+      return false;
 
   len /= 2;
   for (i = 0; i < len; i++)
@@ -147,8 +138,8 @@ posix_time_parse (struct tm *tm, const char *s, unsigned 
int syntax_bits)
   p = pair;
   if (syntax_bits & PDS_LEADING_YEAR)
     {
-      if (year (tm, p, len - 4, syntax_bits))
-        return 1;
+      if (! year (tm, p, len - 4, syntax_bits))
+        return false;
       p += len - 4;
       len = 4;
     }
@@ -163,28 +154,19 @@ posix_time_parse (struct tm *tm, const char *s, unsigned 
int syntax_bits)
   /* Handle any trailing year.  */
   if (syntax_bits & PDS_TRAILING_YEAR)
     {
-      if (year (tm, p, len, syntax_bits))
-        return 1;
+      if (! year (tm, p, len, syntax_bits))
+        return false;
     }
 
   /* Handle seconds.  */
   if (!dot)
-    {
-      tm->tm_sec = 0;
-    }
+    tm->tm_sec = 0;
+  else if (ISDIGIT (dot[1]) && ISDIGIT (dot[2]))
+    tm->tm_sec = 10 * (dot[1] - '0') + dot[2] - '0';
   else
-    {
-      int seconds;
-
-      ++dot;
-      if (!ISDIGIT (dot[0]) || !ISDIGIT (dot[1]))
-        return 1;
-      seconds = 10 * (dot[0] - '0') + dot[1] - '0';
-
-      tm->tm_sec = seconds;
-    }
+    return false;
 
-  return 0;
+  return true;
 }
 
 /* Parse a POSIX-style date, returning true if successful.  */
@@ -197,7 +179,7 @@ posixtime (time_t *p, const char *s, unsigned int 
syntax_bits)
   struct tm const *tm;
   time_t t;
 
-  if (posix_time_parse (&tm0, s, syntax_bits))
+  if (! posix_time_parse (&tm0, s, syntax_bits))
     return false;
 
   tm1 = tm0;
@@ -216,7 +198,9 @@ posixtime (time_t *p, const char *s, unsigned int 
syntax_bits)
     }
 
   /* Reject dates like "September 31" and times like "25:61".
-     Do not reject times that specify "60" as the number of seconds.  */
+     However, allow a seconds count of 60 even in time zones that do
+     not support leap seconds, treating it as the following second;
+     POSIX requires this.  */
   if ((tm0.tm_year ^ tm->tm_year)
       | (tm0.tm_mon ^ tm->tm_mon)
       | (tm0.tm_mday ^ tm->tm_mday)
-- 
1.9.3