/*
* libgit2 "blame" example - shows how to use the blame API
*
* Written by the libgit2 contributors
*
* To the extent possible under law, the author(s) have dedicated all copyright
* and related and neighboring rights to this software to the public domain
* worldwide. This software is distributed without any warranty.
*
* You should have received a copy of the CC0 Public Domain Dedication along
* with this software. If not, see
* <http://creativecommons.org/publicdomain/zero/1.0/>.
*/
#include "common.h"
/**
* This example demonstrates how to invoke the libgit2 blame API to roughly
* simulate the output of `git blame` and a few of its command line arguments.
*/
struct blame_opts {
char *path;
char *commitspec;
int C;
int M;
int start_line;
int end_line;
int F;
};
static void parse_opts(struct blame_opts *o, int argc, char *argv[]);
int lg2_blame(git_repository *repo, int argc, char *argv[])
{
int line, break_on_null_hunk;
git_object_size_t i, rawsize;
char spec[1024] = {0};
struct blame_opts o = {0};
const char *rawdata;
git_revspec revspec = {0};
git_blame_options blameopts = GIT_BLAME_OPTIONS_INIT;
git_blame *blame = NULL;
git_blob *blob;
git_object *obj;
parse_opts(&o, argc, argv);
if (o.M) blameopts.flags |= GIT_BLAME_TRACK_COPIES_SAME_COMMIT_MOVES;
if (o.C) blameopts.flags |= GIT_BLAME_TRACK_COPIES_SAME_COMMIT_COPIES;
if (o.F) blameopts.flags |= GIT_BLAME_FIRST_PARENT;
/**
* The commit range comes in "committish" form. Use the rev-parse API to
* nail down the end points.
*/
if (o.commitspec) {
check_lg2(git_revparse(&revspec, repo, o.commitspec), "Couldn't parse commit spec", NULL);
if (revspec.flags & GIT_REVSPEC_SINGLE) {
git_oid_cpy(&blameopts.newest_commit, git_object_id(revspec.from));
git_object_free(revspec.from);
} else {
git_oid_cpy(&blameopts.oldest_commit, git_object_id(revspec.from));
git_oid_cpy(&blameopts.newest_commit, git_object_id(revspec.to));
git_object_free(revspec.from);
git_object_free(revspec.to);
}
}
/** Run the blame. */
check_lg2(git_blame_file(&blame, repo, o.path, &blameopts), "Blame error", NULL);
/**
* Get the raw data inside the blob for output. We use the
* `committish:path/to/file.txt` format to find it.
*/
if (git_oid_is_zero(&blameopts.newest_commit))
strcpy(spec, "HEAD");
else
git_oid_tostr(spec, sizeof(spec), &blameopts.newest_commit);
strcat(spec, ":");
strcat(spec, o.path);
check_lg2(git_revparse_single(&obj, repo, spec), "Object lookup error", NULL);
check_lg2(git_blob_lookup(&blob, repo, git_object_id(obj)), "Blob lookup error", NULL);
git_object_free(obj);
rawdata = git_blob_rawcontent(blob);
rawsize = git_blob_rawsize(blob);
/** Produce the output. */
line = 1;
i = 0;
break_on_null_hunk = 0;
while (i < rawsize) {
const char *eol = memchr(rawdata + i, '\n', (size_t)(rawsize - i));
char oid[10] = {0};
const git_blame_hunk *hunk = git_blame_get_hunk_byline(blame, line);
if (break_on_null_hunk && !hunk)
break;
if (hunk) {
char sig[128] = {0};
break_on_null_hunk = 1;
git_oid_tostr(oid, 10, &hunk->final_commit_id);
snprintf(sig, 30, "%s <%s>", hunk->final_signature->name, hunk->final_signature->email);
printf("%s ( %-30s %3d) %.*s\n",
oid,
sig,
line,
(int)(eol - rawdata - i),
rawdata + i);
}
i = (int)(eol - rawdata + 1);
line++;
}
/** Cleanup. */
git_blob_free(blob);
git_blame_free(blame);
return 0;
}
/** Tell the user how to make this thing work. */
static void usage(const char *msg, const char *arg)
{
if (msg && arg)
fprintf(stderr, "%s: %s\n", msg, arg);
else if (msg)
fprintf(stderr, "%s\n", msg);
fprintf(stderr, "usage: blame [options] [<commit range>] <path>\n");
fprintf(stderr, "\n");
fprintf(stderr, " <commit range> example: `HEAD~10..HEAD`, or `1234abcd`\n");
fprintf(stderr, " -L <n,m> process only line range n-m, counting from 1\n");
fprintf(stderr, " -M find line moves within and across files\n");
fprintf(stderr, " -C find line copies within and across files\n");
fprintf(stderr, " -F follow only the first parent commits\n");
fprintf(stderr, "\n");
exit(1);
}
/** Parse the arguments. */
static void parse_opts(struct blame_opts *o, int argc, char *argv[])
{
int i;
char *bare_args[3] = {0};
if (argc < 2) usage(NULL, NULL);
for (i=1; i<argc; i++) {
char *a = argv[i];
if (a[0] != '-') {
int i=0;
while (bare_args[i] && i < 3) ++i;
if (i >= 3)
usage("Invalid argument set", NULL);
bare_args[i] = a;
}
else if (!strcmp(a, "--"))
continue;
else if (!strcasecmp(a, "-M"))
o->M = 1;
else if (!strcasecmp(a, "-C"))
o->C = 1;
else if (!strcasecmp(a, "-F"))
o->F = 1;
else if (!strcasecmp(a, "-L")) {
i++; a = argv[i];
if (i >= argc) fatal("Not enough arguments to -L", NULL);
check_lg2(sscanf(a, "%d,%d", &o->start_line, &o->end_line)-2, "-L format error", NULL);
}
else {
/* commit range */
if (o->commitspec) fatal("Only one commit spec allowed", NULL);
o->commitspec = a;
}
}
/* Handle the bare arguments */
if (!bare_args[0]) usage("Please specify a path", NULL);
o->path = bare_args[0];
if (bare_args[1]) {
/* <commitspec> <path> */
o->path = bare_args[1];
o->commitspec = bare_args[0];
}
if (bare_args[2]) {
/* <oldcommit> <newcommit> <path> */
char spec[128] = {0};
o->path = bare_args[2];
sprintf(spec, "%s..%s", bare_args[0], bare_args[1]);
o->commitspec = spec;
}
}
