builtin-bundle - use buffered reads for bundle header

This eliminates all use of byte-at-a-time reading of data in this
function: as Junio noted, a bundle file is seekable so we can
reset the file position to the first part of the pack-file using lseek
after reading the header.

Signed-off-by: Mark Levedahl <mdl123@verizon.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Mark Levedahl 2007-08-10 20:39:24 -04:00 committed by Junio C Hamano
parent 442b67a559
commit 21a02980f9

View File

@ -44,38 +44,21 @@ struct bundle_header {
struct ref_list references;
};
/* this function returns the length of the string */
static int read_string(int fd, char *buffer, int size)
{
int i;
for (i = 0; i < size - 1; i++) {
ssize_t count = xread(fd, buffer + i, 1);
if (count < 0)
return error("Read error: %s", strerror(errno));
if (count == 0) {
i--;
break;
}
if (buffer[i] == '\n')
break;
}
buffer[i + 1] = '\0';
return i + 1;
}
/* returns an fd */
static int read_header(const char *path, struct bundle_header *header) {
char buffer[1024];
int fd = open(path, O_RDONLY);
int fd;
long fpos;
FILE *ffd = fopen(path, "rb");
if (fd < 0)
if (!ffd)
return error("could not open '%s'", path);
if (read_string(fd, buffer, sizeof(buffer)) < 0 ||
if (!fgets(buffer, sizeof(buffer), ffd) ||
strcmp(buffer, bundle_signature)) {
close(fd);
fclose(ffd);
return error("'%s' does not look like a v2 bundle file", path);
}
while (read_string(fd, buffer, sizeof(buffer)) > 0
while (fgets(buffer, sizeof(buffer), ffd)
&& buffer[0] != '\n') {
int is_prereq = buffer[0] == '-';
int offset = is_prereq ? 1 : 0;
@ -97,6 +80,12 @@ static int read_header(const char *path, struct bundle_header *header) {
add_to_ref_list(sha1, isspace(delim) ?
buffer + 41 + offset : "", list);
}
fpos = ftell(ffd);
fclose(ffd);
fd = open(path, O_RDONLY);
if (fd < 0)
return error("could not open '%s'", path);
lseek(fd, fpos, SEEK_SET);
return fd;
}