git-commit-vandalism/rev-parse.c
Linus Torvalds 218e441daf Change parent syntax to "xyz^" instead of "xyz.p"
The ".pN" thing might be a common ending of a tag, and in
contrast, ^ already is a special character for revisions
so use that instead.
2005-06-20 21:06:47 -07:00

179 lines
3.2 KiB
C

/*
* rev-parse.c
*
* Copyright (C) Linus Torvalds, 2005
*/
#include "cache.h"
#include "commit.h"
static int get_extended_sha1(char *name, unsigned char *sha1);
/*
* Some arguments are relevant "revision" arguments,
* others are about output format or other details.
* This sorts it all out.
*/
static int is_rev_argument(const char *arg)
{
static const char *rev_args[] = {
"--max-count=",
"--max-age=",
"--min-age=",
"--merge-order",
NULL
};
const char **p = rev_args;
for (;;) {
const char *str = *p++;
int len;
if (!str)
return 0;
len = strlen(str);
if (!strncmp(arg, str, len))
return 1;
}
}
static int get_parent(char *name, unsigned char *result, int idx)
{
unsigned char sha1[20];
int ret = get_extended_sha1(name, sha1);
struct commit *commit;
struct commit_list *p;
if (ret)
return ret;
commit = lookup_commit_reference(sha1);
if (!commit)
return -1;
if (parse_commit(commit))
return -1;
p = commit->parents;
while (p) {
if (!--idx) {
memcpy(result, p->item->object.sha1, 20);
return 0;
}
p = p->next;
}
return -1;
}
/*
* This is like "get_sha1()", except it allows "sha1 expressions",
* notably "xyz^" for "parent of xyz"
*/
static int get_extended_sha1(char *name, unsigned char *sha1)
{
int parent;
int len = strlen(name);
parent = 1;
if (len > 2 && name[len-1] >= '1' && name[len-1] <= '9') {
parent = name[len-1] - '0';
len--;
}
if (len > 1 && name[len-1] == '^') {
int ret;
name[len-1] = 0;
ret = get_parent(name, sha1, parent);
name[len-1] = '^';
if (!ret)
return 0;
}
return get_sha1(name, sha1);
}
int main(int argc, char **argv)
{
int i, as_is = 0, revs_only = 0, no_revs = 0;
char *def = NULL;
unsigned char sha1[20];
for (i = 1; i < argc; i++) {
char *arg = argv[i];
char *dotdot;
if (as_is) {
printf("%s\n", arg);
continue;
}
if (*arg == '-') {
if (!strcmp(arg, "--")) {
if (def) {
printf("%s\n", def);
def = NULL;
}
if (revs_only)
break;
as_is = 1;
}
if (!strcmp(arg, "--default")) {
if (def)
printf("%s\n", def);
def = argv[i+1];
i++;
continue;
}
if (!strcmp(arg, "--revs-only")) {
revs_only = 1;
continue;
}
if (!strcmp(arg, "--no-revs")) {
no_revs = 1;
continue;
}
if (revs_only | no_revs) {
if (is_rev_argument(arg) != revs_only)
continue;
}
printf("%s\n", arg);
continue;
}
dotdot = strstr(arg, "..");
if (dotdot) {
unsigned char end[20];
char *n = dotdot+2;
*dotdot = 0;
if (!get_extended_sha1(arg, sha1)) {
if (!*n)
n = "HEAD";
if (!get_extended_sha1(n, end)) {
if (no_revs)
continue;
def = NULL;
printf("%s\n", sha1_to_hex(end));
printf("^%s\n", sha1_to_hex(sha1));
continue;
}
}
*dotdot = '.';
}
if (!get_extended_sha1(arg, sha1)) {
if (no_revs)
continue;
def = NULL;
printf("%s\n", sha1_to_hex(sha1));
continue;
}
if (*arg == '^' && !get_extended_sha1(arg+1, sha1)) {
if (no_revs)
continue;
def = NULL;
printf("^%s\n", sha1_to_hex(sha1));
continue;
}
if (def) {
printf("%s\n", def);
def = NULL;
}
if (revs_only)
continue;
printf("%s\n", arg);
}
if (def)
printf("%s\n", def);
return 0;
}