Merge branch 'nd/ls-tree-pathspec'
[gitweb.git] / git.c
diff --git a/git.c b/git.c
index 9efd1a3ec1f2af63fe575f9c755dff685d9b1e51..82d7a1cfee806001c2d8b81a9dc822a513c75451 100644 (file)
--- a/git.c
+++ b/git.c
@@ -14,12 +14,49 @@ const char git_usage_string[] =
        "           <command> [<args>]";
 
 const char git_more_info_string[] =
-       N_("'git help -a' and 'git help -g' lists available subcommands and some\n"
+       N_("'git help -a' and 'git help -g' list available subcommands and some\n"
           "concept guides. See 'git help <command>' or 'git help <concept>'\n"
           "to read about a specific subcommand or concept.");
 
 static struct startup_info git_startup_info;
 static int use_pager = -1;
+static char *orig_cwd;
+static const char *env_names[] = {
+       GIT_DIR_ENVIRONMENT,
+       GIT_WORK_TREE_ENVIRONMENT,
+       GIT_IMPLICIT_WORK_TREE_ENVIRONMENT,
+       GIT_PREFIX_ENVIRONMENT
+};
+static char *orig_env[4];
+static int saved_environment;
+
+static void save_env(void)
+{
+       int i;
+       if (saved_environment)
+               return;
+       saved_environment = 1;
+       orig_cwd = xgetcwd();
+       for (i = 0; i < ARRAY_SIZE(env_names); i++) {
+               orig_env[i] = getenv(env_names[i]);
+               if (orig_env[i])
+                       orig_env[i] = xstrdup(orig_env[i]);
+       }
+}
+
+static void restore_env(void)
+{
+       int i;
+       if (orig_cwd && chdir(orig_cwd))
+               die_errno("could not move to %s", orig_cwd);
+       free(orig_cwd);
+       for (i = 0; i < ARRAY_SIZE(env_names); i++) {
+               if (orig_env[i])
+                       setenv(env_names[i], orig_env[i], 1);
+               else
+                       unsetenv(env_names[i]);
+       }
+}
 
 static void commit_pager_choice(void) {
        switch (use_pager) {
@@ -54,8 +91,7 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
                /*
                 * Check remaining flags.
                 */
-               if (starts_with(cmd, "--exec-path")) {
-                       cmd += 11;
+               if (skip_prefix(cmd, "--exec-path", &cmd)) {
                        if (*cmd == '=')
                                git_set_argv_exec_path(cmd + 1);
                        else {
@@ -92,8 +128,8 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
                                *envchanged = 1;
                        (*argv)++;
                        (*argc)--;
-               } else if (starts_with(cmd, "--git-dir=")) {
-                       setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
+               } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
+                       setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
                        if (envchanged)
                                *envchanged = 1;
                } else if (!strcmp(cmd, "--namespace")) {
@@ -106,8 +142,8 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
                                *envchanged = 1;
                        (*argv)++;
                        (*argc)--;
-               } else if (starts_with(cmd, "--namespace=")) {
-                       setenv(GIT_NAMESPACE_ENVIRONMENT, cmd + 12, 1);
+               } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
+                       setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
                        if (envchanged)
                                *envchanged = 1;
                } else if (!strcmp(cmd, "--work-tree")) {
@@ -120,14 +156,15 @@ static int handle_options(const char ***argv, int *argc, int *envchanged)
                                *envchanged = 1;
                        (*argv)++;
                        (*argc)--;
-               } else if (starts_with(cmd, "--work-tree=")) {
-                       setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
+               } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
+                       setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
                        if (envchanged)
                                *envchanged = 1;
                } else if (!strcmp(cmd, "--bare")) {
-                       static char git_dir[PATH_MAX+1];
+                       char *cwd = xgetcwd();
                        is_bare_repository_cfg = 1;
-                       setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
+                       setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
+                       free(cwd);
                        setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
                        if (envchanged)
                                *envchanged = 1;
@@ -245,8 +282,7 @@ static int handle_alias(int *argcp, const char ***argv)
                                  "trace: alias expansion: %s =>",
                                  alias_command);
 
-               new_argv = xrealloc(new_argv, sizeof(char *) *
-                                   (count + *argcp));
+               REALLOC_ARRAY(new_argv, count + *argcp);
                /* insert after command name */
                memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 
@@ -272,6 +308,7 @@ static int handle_alias(int *argcp, const char ***argv)
  * RUN_SETUP for reading from the configuration file.
  */
 #define NEED_WORK_TREE         (1<<3)
+#define NO_SETUP               (1<<4)
 
 struct cmd_struct {
        const char *cmd;
@@ -290,7 +327,7 @@ static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
        if (!help) {
                if (p->option & RUN_SETUP)
                        prefix = setup_git_directory();
-               if (p->option & RUN_SETUP_GENTLY) {
+               else if (p->option & RUN_SETUP_GENTLY) {
                        int nongit_ok;
                        prefix = setup_git_directory_gently(&nongit_ok);
                }
@@ -352,7 +389,7 @@ static struct cmd_struct commands[] = {
        { "cherry", cmd_cherry, RUN_SETUP },
        { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
        { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
-       { "clone", cmd_clone },
+       { "clone", cmd_clone, NO_SETUP },
        { "column", cmd_column, RUN_SETUP_GENTLY },
        { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
        { "commit-tree", cmd_commit_tree, RUN_SETUP },
@@ -378,8 +415,9 @@ static struct cmd_struct commands[] = {
        { "hash-object", cmd_hash_object },
        { "help", cmd_help },
        { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
-       { "init", cmd_init_db },
-       { "init-db", cmd_init_db },
+       { "init", cmd_init_db, NO_SETUP },
+       { "init-db", cmd_init_db, NO_SETUP },
+       { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP },
        { "log", cmd_log, RUN_SETUP },
        { "ls-files", cmd_ls_files, RUN_SETUP },
        { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
@@ -441,6 +479,7 @@ static struct cmd_struct commands[] = {
        { "upload-archive", cmd_upload_archive },
        { "upload-archive--writer", cmd_upload_archive_writer },
        { "var", cmd_var, RUN_SETUP_GENTLY },
+       { "verify-commit", cmd_verify_commit, RUN_SETUP },
        { "verify-pack", cmd_verify_pack },
        { "verify-tag", cmd_verify_tag, RUN_SETUP },
        { "version", cmd_version },
@@ -448,15 +487,20 @@ static struct cmd_struct commands[] = {
        { "write-tree", cmd_write_tree, RUN_SETUP },
 };
 
-int is_builtin(const char *s)
+static struct cmd_struct *get_builtin(const char *s)
 {
        int i;
        for (i = 0; i < ARRAY_SIZE(commands); i++) {
-               struct cmd_struct *p = commands+i;
+               struct cmd_struct *p = commands + i;
                if (!strcmp(s, p->cmd))
-                       return 1;
+                       return p;
        }
-       return 0;
+       return NULL;
+}
+
+int is_builtin(const char *s)
+{
+       return !!get_builtin(s);
 }
 
 static void handle_builtin(int argc, const char **argv)
@@ -464,6 +508,7 @@ static void handle_builtin(int argc, const char **argv)
        const char *cmd = argv[0];
        int i;
        static const char ext[] = STRIP_EXTENSION;
+       struct cmd_struct *builtin;
 
        if (sizeof(ext) > 1) {
                i = strlen(argv[0]) - strlen(ext);
@@ -480,11 +525,12 @@ static void handle_builtin(int argc, const char **argv)
                argv[0] = cmd = "help";
        }
 
-       for (i = 0; i < ARRAY_SIZE(commands); i++) {
-               struct cmd_struct *p = commands+i;
-               if (strcmp(p->cmd, cmd))
-                       continue;
-               exit(run_builtin(p, argc, argv));
+       builtin = get_builtin(cmd);
+       if (builtin) {
+               if (saved_environment && (builtin->option & NO_SETUP))
+                       restore_env();
+               else
+                       exit(run_builtin(builtin, argc, argv));
        }
 }
 
@@ -539,7 +585,10 @@ static int run_argv(int *argcp, const char ***argv)
                 * of overriding "git log" with "git show" by having
                 * alias.log = show
                 */
-               if (done_alias || !handle_alias(argcp, argv))
+               if (done_alias)
+                       break;
+               save_env();
+               if (!handle_alias(argcp, argv))
                        break;
                done_alias = 1;
        }
@@ -547,6 +596,26 @@ static int run_argv(int *argcp, const char ***argv)
        return done_alias;
 }
 
+/*
+ * Many parts of Git have subprograms communicate via pipe, expect the
+ * upstream of a pipe to die with SIGPIPE when the downstream of a
+ * pipe does not need to read all that is written.  Some third-party
+ * programs that ignore or block SIGPIPE for their own reason forget
+ * to restore SIGPIPE handling to the default before spawning Git and
+ * break this carefully orchestrated machinery.
+ *
+ * Restore the way SIGPIPE is handled to default, which is what we
+ * expect.
+ */
+static void restore_sigpipe_to_default(void)
+{
+       sigset_t unblock;
+
+       sigemptyset(&unblock);
+       sigaddset(&unblock, SIGPIPE);
+       sigprocmask(SIG_UNBLOCK, &unblock, NULL);
+       signal(SIGPIPE, SIG_DFL);
+}
 
 int main(int argc, char **av)
 {
@@ -566,8 +635,12 @@ int main(int argc, char **av)
         */
        sanitize_stdfds();
 
+       restore_sigpipe_to_default();
+
        git_setup_gettext();
 
+       trace_command_performance(argv);
+
        /*
         * "git-xxxx" is the same as "git xxxx", but we obviously:
         *
@@ -578,8 +651,7 @@ int main(int argc, char **av)
         * So we just directly call the builtin handler, and die if
         * that one cannot handle it.
         */
-       if (starts_with(cmd, "git-")) {
-               cmd += 4;
+       if (skip_prefix(cmd, "git-", &cmd)) {
                argv[0] = cmd;
                handle_builtin(argc, argv);
                die("cannot handle %s as a builtin", cmd);
@@ -590,8 +662,8 @@ int main(int argc, char **av)
        argc--;
        handle_options(&argv, &argc, NULL);
        if (argc > 0) {
-               if (starts_with(argv[0], "--"))
-                       argv[0] += 2;
+               /* translate --help and --version into commands */
+               skip_prefix(argv[0], "--", &argv[0]);
        } else {
                /* The user didn't specify a command; give them help */
                commit_pager_choice();