Migrate ODB files to new error handling

This migrates odb.c, odb_loose.c, odb_pack.c and pack.c to
the new style of error handling.  Also got the unix and win32
versions of map.c.  There are some minor changes to other
files but no others were completely converted.

This also contains an update to filebuf so that a zeroed out
filebuf will not think that the fd (== 0) is actually open
(and inadvertently call close() on fd 0 if cleaned up).

Lastly, this was built and tested on win32 and contains a
bunch of fixes for the win32 build which was pretty broken.

Author: arrbee

include/git2/errors.h

@@ -103,7 +103,7 @@ typedef enum {
 	GIT_EOBJCORRUPTED = -28,
 
 	/** The given short oid is ambiguous */
-	GIT_EAMBIGUOUSOIDPREFIX = -29,
+	GIT_EAMBIGUOUS = -29,
 
 	/** Skip and passthrough the given ODB backend */
 	GIT_EPASSTHROUGH = -30,
@@ -128,6 +128,7 @@ typedef enum {
 	GITERR_REPOSITORY,
 	GITERR_CONFIG,
 	GITERR_REGEX,
+	GITERR_ODB
 } git_error_class;
 
 /**

src/blob.c

@@ -78,7 +78,7 @@ static int write_file_stream(git_oid *oid, git_odb *odb, const char *path, git_o
 	char buffer[4096];
 	git_odb_stream *stream = NULL;
 
-	if ((error = git_odb_open_wstream(&stream, odb, file_size, GIT_OBJ_BLOB)) < GIT_SUCCESS)
+	if ((error = git_odb_open_wstream(&stream, odb, (size_t)file_size, GIT_OBJ_BLOB)) < GIT_SUCCESS)
 		return error;
 
 	if ((fd = p_open(path, O_RDONLY)) < 0) {

src/errors.c

@@ -40,7 +40,7 @@ static struct {
 	{GIT_EEXISTS, "A reference with this name already exists"},
 	{GIT_EOVERFLOW, "The given integer literal is too large to be parsed"},
 	{GIT_ENOTNUM, "The given literal is not a valid number"},
-	{GIT_EAMBIGUOUSOIDPREFIX, "The given oid prefix is ambiguous"},
+	{GIT_EAMBIGUOUS, "The given oid prefix is ambiguous"},
 };
 
 const char *git_strerror(int num)
@@ -129,9 +129,29 @@ void giterr_set(int error_class, const char *string, ...)
 
 	/* automatically suffix strerror(errno) for GITERR_OS errors */
 	if (error_class == GITERR_OS) {
-		strncat(error_str, ": ", sizeof(error_str));
-		strncat(error_str, strerror(errno), sizeof(error_str));
-		errno = 0;
+		if (errno != 0) {
+			strncat(error_str, ": ", sizeof(error_str));
+			strncat(error_str, strerror(errno), sizeof(error_str));
+			errno = 0;
+		}
+#ifdef GIT_WIN32
+		else {
+			LPVOID lpMsgBuf;
+			DWORD dw = GetLastError();
+
+			FormatMessage(
+				FORMAT_MESSAGE_ALLOCATE_BUFFER | 
+				FORMAT_MESSAGE_FROM_SYSTEM |
+				FORMAT_MESSAGE_IGNORE_INSERTS,
+				NULL, dw, 0, (LPTSTR) &lpMsgBuf, 0, NULL);
+
+			if (lpMsgBuf) {
+				strncat(error_str, ": ", sizeof(error_str));
+				strncat(error_str, (const char *)lpMsgBuf, sizeof(error_str));
+				LocalFree(lpMsgBuf);
+			}
+		}
+#endif
 	}
 
 	giterr_set_str(error_class, error_str);

src/filebuf.c

@@ -67,6 +67,8 @@ static int lock_file(git_filebuf *file, int flags)
 	if (file->fd < 0)
 		return -1;
 
+	file->fd_is_open = true;
+
 	if ((flags & GIT_FILEBUF_APPEND) && git_path_exists(file->path_original) == true) {
 		git_file source;
 		char buffer[2048];
@@ -94,10 +96,10 @@ static int lock_file(git_filebuf *file, int flags)
 
 void git_filebuf_cleanup(git_filebuf *file)
 {
-	if (file->fd >= 0)
+	if (file->fd_is_open && file->fd >= 0)
 		p_close(file->fd);
 
-	if (file->fd >= 0 && file->path_lock && git_path_exists(file->path_lock) == true)
+	if (file->fd_is_open && file->path_lock && git_path_exists(file->path_lock))
 		p_unlink(file->path_lock);
 
 	if (file->digest)
@@ -239,6 +241,7 @@ int git_filebuf_open(git_filebuf *file, const char *path, int flags)
 			git_buf_free(&tmp_path);
 			goto cleanup;
 		}
+		file->fd_is_open = true;
 
 		/* No original path */
 		file->path_original = NULL;
@@ -308,6 +311,7 @@ int git_filebuf_commit(git_filebuf *file, mode_t mode)
 
 	p_close(file->fd);
 	file->fd = -1;
+	file->fd_is_open = false;
 
 	if (p_chmod(file->path_lock, mode)) {
 		giterr_set(GITERR_OS, "Failed to set attributes for file at '%s'", file->path_lock);

src/filebuf.h

@@ -40,6 +40,7 @@ struct git_filebuf {
 
 	size_t buf_size, buf_pos;
 	git_file fd;
+	bool fd_is_open;
 	int last_error;
 };
 

src/fileops.c

@@ -117,7 +117,7 @@ int git_futils_readbuffer_updated(git_buf *buf, const char *path, time_t *mtime,
 		return fd;
 
 	if (p_fstat(fd, &st) < 0 || S_ISDIR(st.st_mode) || !git__is_sizet(st.st_size+1)) {
-		close(fd);
+		p_close(fd);
 		giterr_set(GITERR_OS, "Invalid regular file stat for '%s'", path);
 		return -1;
 	}
@@ -127,7 +127,7 @@ int git_futils_readbuffer_updated(git_buf *buf, const char *path, time_t *mtime,
 	 * has been modified.
 	 */
 	if (mtime != NULL && *mtime >= st.st_mtime) {
-		close(fd);
+		p_close(fd);
 		return 0;
 	}
 
@@ -139,8 +139,8 @@ int git_futils_readbuffer_updated(git_buf *buf, const char *path, time_t *mtime,
 	git_buf_clear(buf);
 
 	if (git_buf_grow(buf, len + 1) < 0) {
-		close(fd);
-		return GIT_ENOMEM;
+		p_close(fd);
+		return -1;
 	}
 
 	buf->ptr[len] = '\0';
@@ -149,7 +149,7 @@ int git_futils_readbuffer_updated(git_buf *buf, const char *path, time_t *mtime,
 		ssize_t read_size = p_read(fd, buf->ptr, len);
 
 		if (read_size < 0) {
-			close(fd);
+			p_close(fd);
 			giterr_set(GITERR_OS, "Failed to read descriptor for '%s'", path);
 			return -1;
 		}

src/indexer.c

@@ -307,7 +307,7 @@ int git_indexer_write(git_indexer *idx)
 int git_indexer_run(git_indexer *idx, git_indexer_stats *stats)
 {
 	git_mwindow_file *mwf;
-	off_t off = sizeof(struct git_pack_header);
+	git_off_t off = sizeof(struct git_pack_header);
 	int error;
 	struct entry *entry;
 	unsigned int left, processed;
@@ -328,18 +328,18 @@ int git_indexer_run(git_indexer *idx, git_indexer_stats *stats)
 		struct git_pack_entry *pentry;
 		git_mwindow *w = NULL;
 		int i;
-		off_t entry_start = off;
+		git_off_t entry_start = off;
 		void *packed;
 		size_t entry_size;
 
-		entry = git__malloc(sizeof(struct entry));
-		memset(entry, 0x0, sizeof(struct entry));
+		entry = git__calloc(1, sizeof(*entry));
+		GITERR_CHECK_ALLOC(entry);
 
 		if (off > UINT31_MAX) {
 			entry->offset = UINT32_MAX;
 			entry->offset_long = off;
 		} else {
-			entry->offset = off;
+			entry->offset = (uint32_t)off;
 		}
 
 		error = git_packfile_unpack(&obj, idx->pack, &off);
@@ -369,7 +369,7 @@ int git_indexer_run(git_indexer *idx, git_indexer_stats *stats)
 		git_oid_cpy(&entry->oid, &oid);
 		entry->crc = crc32(0L, Z_NULL, 0);
 
-		entry_size = off - entry_start;
+		entry_size = (size_t)(off - entry_start);
 		packed = git_mwindow_open(mwf, &w, entry_start, entry_size, &left);
 		if (packed == NULL) {
 			error = git__rethrow(error, "Failed to open window to read packed data");

src/map.h

@@ -31,6 +31,8 @@ typedef struct { /* memory mapped buffer	*/
 #endif
 } git_map;
 
+extern int validate_map_args(git_map *out, size_t len, int prot, int flags, int fd, git_off_t offset);
+
 extern int p_mmap(git_map *out, size_t len, int prot, int flags, int fd, git_off_t offset);
 extern int p_munmap(git_map *map);
 

src/mwindow.c

@@ -178,8 +178,10 @@ static git_mwindow *new_window(
 	 * window.
 	 */
 
-	if (git_futils_mmap_ro(&w->window_map, fd, w->offset, (size_t)len) < GIT_SUCCESS)
-		goto cleanup;
+	if (git_futils_mmap_ro(&w->window_map, fd, w->offset, (size_t)len) < 0) {
+		git__free(w);
+		return NULL;
+	}
 
 	ctl->mmap_calls++;
 	ctl->open_windows++;
@@ -191,10 +193,6 @@ static git_mwindow *new_window(
 		ctl->peak_open_windows = ctl->open_windows;
 
 	return w;
-
-cleanup:
-	git__free(w);
-	return NULL;
 }
 
 /*
@@ -253,11 +251,10 @@ unsigned char *git_mwindow_open(
 int git_mwindow_file_register(git_mwindow_file *mwf)
 {
 	git_mwindow_ctl *ctl = &GIT_GLOBAL->mem_ctl;
-	int error;
 
 	if (ctl->windowfiles.length == 0 &&
-		(error = git_vector_init(&ctl->windowfiles, 8, NULL)) < GIT_SUCCESS)
-		return error;
+		git_vector_init(&ctl->windowfiles, 8, NULL) < 0)
+		return -1;
 
 	return git_vector_insert(&ctl->windowfiles, mwf);
 }

src/object.c

@@ -92,7 +92,7 @@ int git_object_lookup_prefix(
 	assert(repo && object_out && id);
 
 	if (len < GIT_OID_MINPREFIXLEN)
-		return git__throw(GIT_EAMBIGUOUSOIDPREFIX,
+		return git__throw(GIT_EAMBIGUOUS,
 			"Failed to lookup object. Prefix length is lower than %d.", GIT_OID_MINPREFIXLEN);
 
 	error = git_repository_odb__weakptr(&odb, repo);