git/merge-cache.c
Linus Torvalds 75118b13bc Ass a "merge-cache" helper program to execute a merge on
any unmerged files.

This one doesn't actually do the merging, but it makes it
easy to script the programs that do using it.
2005-04-17 19:52:54 -07:00

128 lines
2.5 KiB
C

#include <sys/types.h>
#include <sys/wait.h>
#include "cache.h"
static const char *pgm = NULL;
static const char *arguments[5];
static void run_program(void)
{
int pid = fork(), status;
if (pid < 0)
die("unable to fork");
if (!pid) {
execlp(pgm, arguments[0],
arguments[1],
arguments[2],
arguments[3],
arguments[4],
NULL);
die("unable to execute '%s'", pgm);
}
if (waitpid(pid, &status, 0) < 0 || !WIFEXITED(status) || WEXITSTATUS(status))
die("merge program failed");
}
static char *create_temp_file(int stage, unsigned char *sha1)
{
static char template[4][50];
char *path = template[stage];
void *buf;
char type[100];
unsigned long size;
int fd;
buf = read_sha1_file(sha1, type, &size);
if (!buf || strcmp(type, "blob"))
die("unable to read blob object %s", sha1_to_hex(sha1));
strcpy(path, ".merge_file_XXXXXX");
fd = mkstemp(path);
if (fd < 0)
die("unable to create temp-file");
if (write(fd, buf, size) != size)
die("unable to write temp-file");
close(fd);
return path;
}
static int merge_entry(int pos, const char *path)
{
int found;
if (pos >= active_nr)
die("merge-cache: %s not in the cache", path);
arguments[0] = pgm;
arguments[1] = "";
arguments[2] = "";
arguments[3] = "";
arguments[4] = path;
found = 0;
do {
struct cache_entry *ce = active_cache[pos];
int stage = ce_stage(ce);
if (strcmp(ce->name, path))
break;
found++;
arguments[stage] = create_temp_file(stage, ce->sha1);
} while (++pos < active_nr);
if (!found)
die("merge-cache: %s not in the cache", path);
run_program();
return found;
}
static void merge_file(const char *path)
{
int pos = cache_name_pos(path, strlen(path));
/*
* If it already exists in the cache as stage0, it's
* already merged and there is nothing to do.
*/
if (pos < 0)
merge_entry(-pos-1, path);
}
static void merge_all(void)
{
int i;
for (i = 0; i < active_nr; i++) {
struct cache_entry *ce = active_cache[i];
if (!ce_stage(ce))
continue;
i += merge_entry(i, ce->name)-1;
}
}
int main(int argc, char **argv)
{
int i, force_file = 0;
if (argc < 3)
usage("merge-cache <merge-program> (-a | <filename>*)");
read_cache();
pgm = argv[1];
for (i = 2; i < argc; i++) {
char *arg = argv[i];
if (!force_file && *arg == '-') {
if (!strcmp(arg, "--")) {
force_file = 1;
continue;
}
if (!strcmp(arg, "-a")) {
merge_all();
continue;
}
die("merge-cache: unknown option %s", arg);
}
merge_file(arg);
}
return 0;
}