Bug#533513: graphicsmagick: FTBFS on hurd-i386 due to unconditional PATH_MAX usage

[Samuel Thibault]

Package: graphicsmagick
Version: 1.3.5-5
Severity: important
Tags: patch

Hello,

graphicsmagick currently FTBFS on hurd-i386 because it unconditionally
uses PATH_MAX, while POSIX says that this may not be defined when there
is no such limitation in the system, which is the case for the Hurd. The
attached patch fixes this.

Samuel

-- System Information:
Debian Release: squeeze/sid
  APT prefers testing
  APT policy: (990, 'testing'), (500, 'unstable'), (500, 'stable'), (1, 
'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.30 (SMP w/2 CPU cores)
Locale: LANG=fr_FR.UTF-8, LC_CTYPE=fr_FR.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash

-- 
Samuel Thibault <samuel.thiba...@fnac.net>
<O> ?a peut ?tre une madeleine ? sous munitions (avec des composants,
par exemple)
 -+- #runtime -+-

--- graphicsmagick-1.3.5.orig/magick/utility.c
+++ graphicsmagick-1.3.5/magick/utility.c
@@ -1255,32 +1255,52 @@
       some other systems use compatible schemes.
     */
     int
-      length;
+      length,
+      ret;
 
     long
       pid;
 
     char 
-      link_path[MaxTextExtent],
-      real_path[PATH_MAX+1];
+      link_path[MaxTextExtent];
+
+    char *
+      real_path = NULL;
+
+    struct stat
+      linkbuf;
 
     pid=(long) getpid();
     /* Linux format */
     FormatString(link_path,"/proc/%ld/exe",pid);
-    length=readlink(link_path, real_path, PATH_MAX);
-    if (length == -1)
+    ret = lstat(link_path, &linkbuf);
+    if (ret == 0) 
+      {
+        real_path = malloc(linkbuf.st_size + 1);
+        length=readlink(link_path, real_path, linkbuf.st_size);
+      }
+    if ((ret != 0) || (length == -1))
       {
         /* Try FreeBSD format */
         FormatString(link_path,"/proc/%ld/file",pid);
-        length=readlink(link_path, real_path, PATH_MAX);
+        ret = lstat(link_path, &linkbuf);
+        if (ret == 0)
+          {
+            real_path = realloc(real_path, linkbuf.st_size + 1);
+            length=readlink(link_path, real_path, linkbuf.st_size);
+          }
       }
-    if ((length > 0) && (length <= PATH_MAX))
+    if ((ret == 0) && (length > 0) && (length <= linkbuf.st_size))
       {
         real_path[length]=0;
         if (strlcpy(path,real_path,MaxTextExtent) < MaxTextExtent)
           if (IsAccessible(path))
-            return(MagickPass);
+            {
+              free(real_path);
+              return(MagickPass);
+            }
       }
+    free(real_path);
   }
 #endif
   return(MagickFail);