Simon Josefsson <[EMAIL PROTECTED]> writes:
> --- read-file.c 16 Jun 2006 21:26:36 +0200 1.1
> +++ read-file.c 17 Jun 2006 18:22:29 +0200
> @@ -43,6 +43,9 @@
> if (!buf)
> return NULL;
>
> + if (ferror (stream))
> + return NULL;
> +
> while (!feof (stream))
> {
> size_t count;
But that would leak memory and would cause errno to contain junk on
failure, even on a POSIX host.
How about the following patch instead? It fixes a few other minor
glitches I spotted. I think it addresses Larry Jones's objections as
well, since it causes the code to always invoke 'read'; on hosts
conforming to the C Standard this is fine, and on other hosts where
feof/ferror isn't sticky, the usual convention is to retry the read
anyway, so it's better in that case. I haven't tested it, though.
2006-06-19 Paul Eggert <[EMAIL PROTECTED]>
* read-file.c (fread_file): Start with buffer allocation of
0 bytes rather than 1 byte; this simplifies the code.
Don't invoke feof; it's not needed. Refactor to avoid duplicate
code to free buffer and save/restore errno.
(internal_read_file): Remove unused local.
--- read-file.c.~1.1.~ 2006-06-16 12:40:12.000000000 -0700
+++ read-file.c 2006-06-19 01:10:16.000000000 -0700
@@ -36,16 +36,15 @@
char *
fread_file (FILE * stream, size_t * length)
{
- char *buf = malloc (1);
- size_t alloc = 1;
+ char *buf = NULL;
+ size_t alloc = 0;
size_t size = 0;
+ int save_errno;
- if (!buf)
- return NULL;
-
- while (!feof (stream))
+ for (;;)
{
size_t count;
+ size_t requested;
if (size + BUFSIZ + 1 > alloc)
{
@@ -58,32 +57,31 @@ fread_file (FILE * stream, size_t * leng
new_buf = realloc (buf, alloc);
if (!new_buf)
{
- int save_errno = errno;
- free (buf);
- errno = save_errno;
- return NULL;
+ save_errno = errno;
+ break;
}
buf = new_buf;
}
- count = fread (buf + size, 1, alloc - size - 1, stream);
+ requested = alloc - size - 1;
+ count = fread (buf + size, 1, requested, stream);
size += count;
- if (ferror (stream))
+ if (count != requested)
{
- int save_errno = errno;
- free (buf);
- errno = save_errno;
- return NULL;
+ save_errno = errno;
+ if (ferror (stream))
+ break;
+ buf[size] = '\0';
+ *length = size;
+ return buf;
}
}
- buf[size] = '\0';
-
- *length = size;
-
- return buf;
+ free (buf);
+ errno = save_errno;
+ return NULL;
}
static char *
@@ -92,7 +90,6 @@ internal_read_file (const char *filename
FILE *stream = fopen (filename, mode);
char *out;
int save_errno;
- int rc;
if (!stream)
return NULL;
