/*

* This example demonstrates the libgit2 rev walker APIs to roughly

* simulate the output of 'git log -1 filename'.

*/

#include "common.h"

#include <sys/stat.h>

#include <sys/time.h>

/* log_state represents walker being configured while handling options */

struct log_state {

};

static struct log_state s;

/* Helper to find how many files in a commit changed from its nth parent. */

static int match_with_parent(git_commit *commit, int i, git_diff_options *opts)

{

git_commit *parent;

git_tree *a, *b;

git_diff *diff;

int ndeltas;

check_lg2(

git_commit_parent(&parent, commit, (size_t)i), "Get parent", NULL);

check_lg2(git_commit_tree(&a, parent), "Tree for parent", NULL);

check_lg2(git_commit_tree(&b, commit), "Tree for commit", NULL);

check_lg2(

git_diff_tree_to_tree(&diff, git_commit_owner(commit), a, b, opts),

"Checking diff between parent and commit", NULL);

ndeltas = (int)git_diff_num_deltas(diff);

git_diff_free(diff);

git_tree_free(a);

git_tree_free(b);

git_commit_free(parent);

return ndeltas > 0;

}

/** Helper to format a git_time value like Git. */

static void print_time(const git_time *intime, const char *prefix)

{

char sign, out[32];

struct tm *intm;

int offset, hours, minutes;

time_t t;

offset = intime->offset;

if (offset < 0) {

sign = '-';

offset = -offset;

} else {

sign = '+';

}

hours = offset / 60;

minutes = offset % 60;

t = (time_t)intime->time + (intime->offset * 60);

intm = gmtime(&t);

strftime(out, sizeof(out), "%a %b %e %T %Y", intm);

printf("%s%s %c%02d%02d\n", prefix, out, sign, hours, minutes);

}

/** Helper to print a commit object. */

static void print_commit(git_commit *commit)

{

char buf[GIT_OID_HEXSZ + 1];

int i, count;

const git_signature *sig;

const char *scan, *eol;

git_oid_tostr(buf, sizeof(buf), git_commit_id(commit));

printf("commit %s\n", buf);

if ((count = (int)git_commit_parentcount(commit)) > 1) {

printf("Merge:");

for (i = 0; i < count; ++i) {

git_oid_tostr(buf, 8, git_commit_parent_id(commit, i));

printf(" %s", buf);

}

printf("\n");

}

if ((sig = git_commit_author(commit)) != NULL) {

printf("Author: %s <%s>\n", sig->name, sig->email);

print_time(&sig->when, "Date: ");

}

printf("\n");

for (scan = git_commit_message(commit); scan && *scan; ) {

for (eol = scan; *eol && *eol != '\n'; ++eol) /* find eol */;

printf(" %.*s\n", (int)(eol - scan), scan);

scan = *eol ? eol + 1 : NULL;

}

printf("\n");

}

/* Helper to get the latest commit of the specified file */

int git_show_last_commit(char *filename)

{

git_oid oid;

git_commit *commit = NULL;

/* Set up pathspec. */

git_diff_options diffopts = GIT_DIFF_OPTIONS_INIT;

diffopts.pathspec.strings = &filename;

diffopts.pathspec.count = 1;

/* Use the revwalker to traverse the history. */

check_lg2(git_revwalk_push_ref(s.walker, s.ref),

"Could not find repository reference", NULL);

for (; !git_revwalk_next(&oid, s.walker); git_commit_free(commit)) {

check_lg2(git_commit_lookup(&commit, s.repo, &oid),

"Failed to look up commit", NULL);

int parents = (int)git_commit_parentcount(commit);

int unmatched = parents;

if (parents == 0) {

git_tree *tree;

git_pathspec *ps;

check_lg2(git_commit_tree(&tree, commit), "Get tree", NULL);

check_lg2(git_pathspec_new(&ps, &diffopts.pathspec),

"Building pathspec", NULL);

if (git_pathspec_match_tree(

NULL, tree, GIT_PATHSPEC_NO_MATCH_ERROR, ps) != 0)

unmatched = 1;

git_pathspec_free(ps);

git_tree_free(tree);

} else {

int i;

for (i = 0; i < parents; ++i) {

if (match_with_parent(commit, i, &diffopts))

unmatched--;

}

}

if (unmatched > 0)

continue;

print_commit(commit);

git_commit_free(commit);

break;

}

git_revwalk_reset(s.walker);

return 0;

}

int main(int argc, char **argv)

{

struct stat st;

struct timeval start, end;

char filepath[1024], repodir[64];

char *dirpath, *filename, *ref = NULL;

if (argc != 3) {

fprintf(stderr, "Usage: ./log dirpath filename\n");

exit(-1);

}

dirpath = argv[1];

filename = argv[2];

strcpy(repodir, dirpath);

strcat(repodir, "/.git");

strcpy(filepath, dirpath);

strcat(filepath, "/");

strcat(filepath, filename);

if (stat(filepath, &st) < 0) {

fprintf(stderr, "Not valid file path: \"%s\"!\n", filepath);

exit(-2);

}

memset(&s, 0, sizeof(s));

s.sorting = GIT_SORT_TIME;

s.hide = 0;

s.repodir = strlen(repodir) > 0 ? repodir : "/tmp/git/.git";

s.ref = ref ? ref : "refs/heads/master";

/* Init libgit2 library */

git_libgit2_init();

/* Open repo. */

check_lg2(git_repository_open_ext(&s.repo, s.repodir, 0, NULL),

"Could not open repository", s.repodir);

/* Create revwalker. */

check_lg2(git_revwalk_new(&s.walker, s.repo),

"Could not create revision walker", NULL);

git_revwalk_sorting(s.walker, s.sorting);

/* Show file's latest commit. */

printf("filename: %s\n", filename);

gettimeofday(&start, NULL);

git_show_last_commit(filename);

gettimeofday(&end, NULL);

printf("time span: %ld(ms)\n", (end.tv_sec - start.tv_sec) * 1000 + \

(end.tv_usec - start.tv_usec) / 1000);

git_revwalk_free(s.walker);

git_repository_free(s.repo);

git_libgit2_shutdown();

return 0;

}