From: Arnaud Giersch <arnaud.giersch@iut-bm.univ-fcomte.fr>
Date: Mon, 4 Feb 2013 14:54:29 +0000 (+0100)
Subject: Rewrite xbt_getline.
X-Git-Tag: v3_9_90~510^2~52
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/422c6b5a12ddeca39e50a0c9ec674cec1b104c0a

Rewrite xbt_getline.

* fix a buffer overflow
* correctly return -1 when nothing can be read
---

diff --git a/src/xbt/xbt_str.c b/src/xbt/xbt_str.c
index 2fad5bf71b..9247f2dd35 100644
--- a/src/xbt/xbt_str.c
+++ b/src/xbt/xbt_str.c
@@ -539,39 +539,32 @@ char *xbt_str_join_array(const char *const *strs, const char *sep)
  * In either case, on a successful call, *buf and *n will be updated to reflect
  * the buffer address and allocated size respectively.
  */
-ssize_t xbt_getline(char **buf, size_t * n, FILE * stream)
+ssize_t xbt_getline(char **buf, size_t *n, FILE *stream)
 {
-  size_t i;
+  ssize_t i;
   int ch;
 
+  ch = getc(stream);
+  if (ferror(stream) || feof(stream))
+    return -1;
+
   if (!*buf) {
-    *buf = xbt_malloc(512);
     *n = 512;
+    *buf = xbt_malloc(*n);
   }
 
-  if (feof(stream))
-    return (ssize_t) - 1;
-
-  for (i = 0; (ch = fgetc(stream)) != EOF; i++) {
-
-    if (i >= (*n) + 1)
+  i = 0;
+  do {
+    if (i == *n)
       *buf = xbt_realloc(*buf, *n += 512);
-
-    (*buf)[i] = ch;
-
-    if ((*buf)[i] == '\n') {
-      i++;
-      (*buf)[i] = '\0';
-      break;
-    }
-  }
+    (*buf)[i++] = ch;
+  } while (ch != '\n' && (ch = getc(stream)) != EOF);
 
   if (i == *n)
     *buf = xbt_realloc(*buf, *n += 1);
-
   (*buf)[i] = '\0';
 
-  return (ssize_t) i;
+  return i;
 }
 
 /*