[PATCH 2/2] Correct some sizeof(size_t) != sizeof(unsigned long) typing errors
- From
Shawn O. Pearce <spearce@spearce.org>
- Date
- Oct 21, 2007, 05:25 UTC
- Message-ID
- <20071021052537.GB31927@spearce.org>
On at least one system I've used recently sizeof(size_t) == 4 and sizeof(unsigned long) == 8. Trying to pass a pointer to an 8 byte value into strbuf_detach() causes problems as the function is expecting an address for a 4 byte result location. Writing only 4 bytes here will leave the other 4 bytes unitialized and may cause problems when the caller evalutes the result.
I am introducing strbuf_detach_ul() as a variant that takes its size as an unsigned long rather than as a size_t. This approach is shorter than fixing all of the callers to use their own temporary size_t value for the call.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org> --- builtin-apply.c | 2 +- builtin-archive.c | 2 +- diff.c | 4 ++-- entry.c | 2 +- strbuf.h | 8 +++++++- test-delta.c | 3 ++- 6 files changed, 14 insertions(+), 7 deletions(-)
diff --git a/builtin-apply.c b/builtin-apply.c index 05c6bc3..022f916 100644 --- a/builtin-apply.c +++ b/builtin-apply.c @@ -1955,7 +1955,7 @@ static int apply_data(struct patch *patch, struct stat *st, struct cache_entry * if (apply_fragments(&buf, patch) < 0) return -1; /* note with --reject this succeeds. */ - patch->result = strbuf_detach(&buf, &patch->resultsize); + patch->result = strbuf_detach_ul(&buf, &patch->resultsize); if (0 < patch->is_delete && patch->resultsize) return error("removal patch leaves file contents"); diff --git a/builtin-archive.c b/builtin-archive.c index 04385de..46d5de0 100644 --- a/builtin-archive.c +++ b/builtin-archive.c @@ -153,7 +153,7 @@ void *sha1_file_to_archive(const char *path, const unsigned char *sha1, strbuf_attach(&buf, buffer, *sizep, *sizep + 1); convert_to_working_tree(path, buf.buf, buf.len, &buf); convert_to_archive(path, buf.buf, buf.len, &buf, commit); - buffer = strbuf_detach(&buf, sizep); + buffer = strbuf_detach_ul(&buf, sizep); } return buffer; diff --git a/diff.c b/diff.c index 6648e01..6fd0c0a 100644 --- a/diff.c +++ b/diff.c @@ -1519,7 +1519,7 @@ static int populate_from_stdin(struct diff_filespec *s) strerror(errno)); s->should_munmap = 0; - s->data = strbuf_detach(&buf, &s->size); + s->data = strbuf_detach_ul(&buf, &s->size); s->should_free = 1; return 0; } @@ -1611,7 +1611,7 @@ int diff_populate_filespec(struct diff_filespec *s, int size_only) if (convert_to_git(s->path, s->data, s->size, &buf)) { munmap(s->data, s->size); s->should_munmap = 0; - s->data = strbuf_detach(&buf, &s->size); + s->data = strbuf_detach_ul(&buf, &s->size); s->should_free = 1; } } diff --git a/entry.c b/entry.c index 98f5f6d..d36a0bb 100644 --- a/entry.c +++ b/entry.c @@ -120,7 +120,7 @@ static int write_entry(struct cache_entry *ce, char *path, const struct checkout strbuf_init(&buf, 0); if (convert_to_working_tree(ce->name, new, size, &buf)) { free(new); - new = strbuf_detach(&buf, &size); + new = strbuf_detach_ul(&buf, &size); } if (to_tempfile) { diff --git a/strbuf.h b/strbuf.h index 9b9e861..d6d6bd0 100644 --- a/strbuf.h +++ b/strbuf.h @@ -52,7 +52,13 @@ struct strbuf { /*----- strbuf life cycle -----*/ extern void strbuf_init(struct strbuf *, size_t); extern void strbuf_release(struct strbuf *); -extern char *strbuf_detach(struct strbuf *, size_t *); +extern char *strbuf_detach(struct strbuf *, unsigned long *); +static inline char *strbuf_detach_ul(struct strbuf *a, unsigned long *n) { + size_t len; + char *res = strbuf_detach(a, &len); + *n = len; + return res; +} extern void strbuf_attach(struct strbuf *, void *, size_t, size_t); static inline void strbuf_swap(struct strbuf *a, struct strbuf *b) { struct strbuf tmp = *a; diff --git a/test-delta.c b/test-delta.c index 3d885ff..018e7dc 100644 --- a/test-delta.c +++ b/test-delta.c @@ -20,7 +20,8 @@ int main(int argc, char *argv[]) int fd; struct stat st; void *from_buf, *data_buf, *out_buf; - unsigned long from_size, data_size, out_size; + unsigned long from_size, data_size; + size_t out_size; if (argc != 5 || (strcmp(argv[1], "-d") && strcmp(argv[1], "-p"))) { fprintf(stderr, "Usage: %s\n", usage_str);
-- 1.5.3.4.1270.g2fe543