2004-11-22  Stepan Kasal  <address@hidden>

	This is a variant of Jim Meyering's patch:
	When grep runs out of memory, don't abort the entire command,
	but rather just the affected command line argument(s).

	* src/grep.c (reset): Allocate a new buffer whenever buffer == NULL.
	(buffer, pagesize): Initialize, so that the code in reset works.
	(fillbuf): If the size of the buffer overflows size_t, free the
	  buffer and exit with errno=ENOMEM; if malloc fails, exit with the
	  errno it gave us, freeing the buffer first.
	  

Index: src/grep.c
===================================================================
RCS file: /cvsroot/grep/grep/src/grep.c,v
retrieving revision 1.85
diff -u -p -r1.85 grep.c
--- src/grep.c	22 Nov 2004 09:53:26 -0000	1.85
+++ src/grep.c	22 Nov 2004 16:01:52 -0000
@@ -211,13 +211,13 @@ context_length_arg (char const *str, int
    all reads aligned on a page boundary and multiples of the
    page size, unless a read yields a partial page.  */
 
-static char *buffer;		/* Base of buffer. */
+static char *buffer = NULL;	/* Base of buffer. */
 static size_t bufalloc;		/* Allocated buffer size, counting slop. */
 #define INITIAL_BUFSIZE 32768	/* Initial buffer size, not counting slop. */
 static int bufdesc;		/* File descriptor. */
 static char *bufbeg;		/* Beginning of user-visible stuff. */
 static char *buflim;		/* Limit of user-visible stuff. */
-static size_t pagesize;		/* alignment of memory pages */
+static size_t pagesize = 0;		/* alignment of memory pages */
 static off_t bufoffset;		/* Read offset; defined on regular files.  */
 static off_t after_last_match;	/* Pointer after last matching line that
 				   would have been output if we were
@@ -242,11 +242,14 @@ static off_t initial_bufoffset;	/* Initi
 static int
 reset (int fd, char const *file, struct stats *stats)
 {
-  if (! pagesize)
+  if (buffer == NULL)
     {
-      pagesize = getpagesize ();
-      if (pagesize == 0 || 2 * pagesize + 1 <= pagesize)
-	abort ();
+      if (pagesize == 0)
+	{
+	  pagesize = getpagesize ();
+	  if (pagesize == 0 || 2 * pagesize + 1 <= pagesize)
+	    abort ();
+	}
       bufalloc = ALIGN_TO (INITIAL_BUFSIZE, pagesize) + pagesize + 1;
       buffer = xmalloc (bufalloc);
     }
@@ -313,7 +316,12 @@ fillbuf (size_t save, struct stats const
       /* Grow newsize until it is at least as great as minsize.  */
       for (newsize = bufalloc - pagesize - 1; newsize < minsize; newsize *= 2)
 	if (newsize * 2 < newsize || newsize * 2 + pagesize + 1 < newsize * 2)
-	  xalloc_die ();
+	  {
+	    free (buffer);
+	    buffer = NULL;
+	    errno = ENOMEM;
+	    return 0;
+	  }
 
       /* Try not to allocate more memory than the file size indicates,
 	 as that might cause unnecessary memory exhaustion if the file
@@ -335,7 +343,15 @@ fillbuf (size_t save, struct stats const
 	 for byte sentinels fore and aft.  */
       newalloc = newsize + pagesize + 1;
 
-      newbuf = bufalloc < newalloc ? xmalloc (bufalloc = newalloc) : buffer;
+      newbuf = bufalloc < newalloc ? malloc (bufalloc = newalloc) : buffer;
+      if (newbuf == NULL)
+	{
+	  int saved_errno = errno;
+	  free (buffer);
+	  buffer = NULL;
+	  errno = saved_errno;
+	  return 0;
+	}
       readbuf = ALIGN_TO (newbuf + 1 + save, pagesize);
       bufbeg = readbuf - save;
       memmove (bufbeg, buffer + saved_offset, save);