git/git.c
Theodore Ts'o dfd42a3c62 Allow aliases to expand to shell commands
If the alias expansion is prefixed with an exclamation point, treat
it as a shell command which is run using system(3).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2007-02-10 22:46:34 -08:00

415 lines
11 KiB
C

#include "builtin.h"
#include "exec_cmd.h"
#include "cache.h"
#include "quote.h"
const char git_usage_string[] =
"git [--version] [--exec-path[=GIT_EXEC_PATH]] [-p|--paginate] [--bare] [--git-dir=GIT_DIR] [--help] COMMAND [ARGS]";
static void prepend_to_path(const char *dir, int len)
{
const char *old_path = getenv("PATH");
char *path;
int path_len = len;
if (!old_path)
old_path = "/usr/local/bin:/usr/bin:/bin";
path_len = len + strlen(old_path) + 1;
path = xmalloc(path_len + 1);
memcpy(path, dir, len);
path[len] = ':';
memcpy(path + len + 1, old_path, path_len - len);
setenv("PATH", path, 1);
free(path);
}
static int handle_options(const char*** argv, int* argc)
{
int handled = 0;
while (*argc > 0) {
const char *cmd = (*argv)[0];
if (cmd[0] != '-')
break;
/*
* For legacy reasons, the "version" and "help"
* commands can be written with "--" prepended
* to make them look like flags.
*/
if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
break;
/*
* Check remaining flags.
*/
if (!strncmp(cmd, "--exec-path", 11)) {
cmd += 11;
if (*cmd == '=')
git_set_exec_path(cmd + 1);
else {
puts(git_exec_path());
exit(0);
}
} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
setup_pager();
} else if (!strcmp(cmd, "--git-dir")) {
if (*argc < 2) {
fprintf(stderr, "No directory given for --git-dir.\n" );
usage(git_usage_string);
}
setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
(*argv)++;
(*argc)--;
} else if (!strncmp(cmd, "--git-dir=", 10)) {
setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
} else if (!strcmp(cmd, "--bare")) {
static char git_dir[PATH_MAX+1];
setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 1);
} else {
fprintf(stderr, "Unknown option: %s\n", cmd);
usage(git_usage_string);
}
(*argv)++;
(*argc)--;
handled++;
}
return handled;
}
static const char *alias_command;
static char *alias_string;
static int git_alias_config(const char *var, const char *value)
{
if (!strncmp(var, "alias.", 6) && !strcmp(var + 6, alias_command)) {
alias_string = xstrdup(value);
}
return 0;
}
static int split_cmdline(char *cmdline, const char ***argv)
{
int src, dst, count = 0, size = 16;
char quoted = 0;
*argv = malloc(sizeof(char*) * size);
/* split alias_string */
(*argv)[count++] = cmdline;
for (src = dst = 0; cmdline[src];) {
char c = cmdline[src];
if (!quoted && isspace(c)) {
cmdline[dst++] = 0;
while (cmdline[++src]
&& isspace(cmdline[src]))
; /* skip */
if (count >= size) {
size += 16;
*argv = xrealloc(*argv, sizeof(char*) * size);
}
(*argv)[count++] = cmdline + dst;
} else if(!quoted && (c == '\'' || c == '"')) {
quoted = c;
src++;
} else if (c == quoted) {
quoted = 0;
src++;
} else {
if (c == '\\' && quoted != '\'') {
src++;
c = cmdline[src];
if (!c) {
free(*argv);
*argv = NULL;
return error("cmdline ends with \\");
}
}
cmdline[dst++] = c;
src++;
}
}
cmdline[dst] = 0;
if (quoted) {
free(*argv);
*argv = NULL;
return error("unclosed quote");
}
return count;
}
static int handle_alias(int *argcp, const char ***argv)
{
int nongit = 0, ret = 0, saved_errno = errno;
const char *subdir;
int count, option_count;
const char** new_argv;
subdir = setup_git_directory_gently(&nongit);
alias_command = (*argv)[0];
git_config(git_alias_config);
if (alias_string) {
if (alias_string[0] == '!') {
trace_printf("trace: alias to shell cmd: %s => %s\n",
alias_command, alias_string + 1);
ret = system(alias_string + 1);
if (ret >= 0 && WIFEXITED(ret) &&
WEXITSTATUS(ret) != 127)
exit(WEXITSTATUS(ret));
die("Failed to run '%s' when expanding alias '%s'\n",
alias_string + 1, alias_command);
}
count = split_cmdline(alias_string, &new_argv);
option_count = handle_options(&new_argv, &count);
memmove(new_argv - option_count, new_argv,
count * sizeof(char *));
new_argv -= option_count;
if (count < 1)
die("empty alias for %s", alias_command);
if (!strcmp(alias_command, new_argv[0]))
die("recursive alias: %s", alias_command);
trace_argv_printf(new_argv, count,
"trace: alias expansion: %s =>",
alias_command);
new_argv = xrealloc(new_argv, sizeof(char*) *
(count + *argcp + 1));
/* insert after command name */
memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
new_argv[count+*argcp] = NULL;
*argv = new_argv;
*argcp += count - 1;
ret = 1;
}
if (subdir)
chdir(subdir);
errno = saved_errno;
return ret;
}
const char git_version_string[] = GIT_VERSION;
#define RUN_SETUP (1<<0)
#define USE_PAGER (1<<1)
/*
* require working tree to be present -- anything uses this needs
* RUN_SETUP for reading from the configuration file.
*/
#define NOT_BARE (1<<2)
static void handle_internal_command(int argc, const char **argv, char **envp)
{
const char *cmd = argv[0];
static struct cmd_struct {
const char *cmd;
int (*fn)(int, const char **, const char *);
int option;
} commands[] = {
{ "add", cmd_add, RUN_SETUP | NOT_BARE },
{ "annotate", cmd_annotate, USE_PAGER },
{ "apply", cmd_apply },
{ "archive", cmd_archive },
{ "blame", cmd_blame, RUN_SETUP },
{ "branch", cmd_branch, RUN_SETUP },
{ "cat-file", cmd_cat_file, RUN_SETUP },
{ "checkout-index", cmd_checkout_index, RUN_SETUP },
{ "check-ref-format", cmd_check_ref_format },
{ "cherry", cmd_cherry, RUN_SETUP },
{ "commit-tree", cmd_commit_tree, RUN_SETUP },
{ "config", cmd_config },
{ "count-objects", cmd_count_objects, RUN_SETUP },
{ "describe", cmd_describe, RUN_SETUP },
{ "diff", cmd_diff, RUN_SETUP | USE_PAGER },
{ "diff-files", cmd_diff_files, RUN_SETUP },
{ "diff-index", cmd_diff_index, RUN_SETUP },
{ "diff-stages", cmd_diff_stages, RUN_SETUP },
{ "diff-tree", cmd_diff_tree, RUN_SETUP },
{ "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
{ "for-each-ref", cmd_for_each_ref, RUN_SETUP },
{ "format-patch", cmd_format_patch, RUN_SETUP },
{ "fsck", cmd_fsck, RUN_SETUP },
{ "fsck-objects", cmd_fsck, RUN_SETUP },
{ "get-tar-commit-id", cmd_get_tar_commit_id },
{ "grep", cmd_grep, RUN_SETUP },
{ "help", cmd_help },
{ "init", cmd_init_db },
{ "init-db", cmd_init_db },
{ "log", cmd_log, RUN_SETUP | USE_PAGER },
{ "ls-files", cmd_ls_files, RUN_SETUP },
{ "ls-tree", cmd_ls_tree, RUN_SETUP },
{ "mailinfo", cmd_mailinfo },
{ "mailsplit", cmd_mailsplit },
{ "merge-file", cmd_merge_file },
{ "mv", cmd_mv, RUN_SETUP | NOT_BARE },
{ "name-rev", cmd_name_rev, RUN_SETUP },
{ "pack-objects", cmd_pack_objects, RUN_SETUP },
{ "pickaxe", cmd_blame, RUN_SETUP | USE_PAGER },
{ "prune", cmd_prune, RUN_SETUP },
{ "prune-packed", cmd_prune_packed, RUN_SETUP },
{ "push", cmd_push, RUN_SETUP },
{ "read-tree", cmd_read_tree, RUN_SETUP },
{ "reflog", cmd_reflog, RUN_SETUP },
{ "repo-config", cmd_config },
{ "rerere", cmd_rerere, RUN_SETUP },
{ "rev-list", cmd_rev_list, RUN_SETUP },
{ "rev-parse", cmd_rev_parse, RUN_SETUP },
{ "rm", cmd_rm, RUN_SETUP | NOT_BARE },
{ "runstatus", cmd_runstatus, RUN_SETUP | NOT_BARE },
{ "shortlog", cmd_shortlog, RUN_SETUP | USE_PAGER },
{ "show-branch", cmd_show_branch, RUN_SETUP },
{ "show", cmd_show, RUN_SETUP | USE_PAGER },
{ "stripspace", cmd_stripspace },
{ "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
{ "tar-tree", cmd_tar_tree },
{ "unpack-objects", cmd_unpack_objects, RUN_SETUP },
{ "update-index", cmd_update_index, RUN_SETUP },
{ "update-ref", cmd_update_ref, RUN_SETUP },
{ "upload-archive", cmd_upload_archive },
{ "version", cmd_version },
{ "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
{ "write-tree", cmd_write_tree, RUN_SETUP },
{ "verify-pack", cmd_verify_pack },
{ "show-ref", cmd_show_ref, RUN_SETUP },
{ "pack-refs", cmd_pack_refs, RUN_SETUP },
};
int i;
/* Turn "git cmd --help" into "git help cmd" */
if (argc > 1 && !strcmp(argv[1], "--help")) {
argv[1] = argv[0];
argv[0] = cmd = "help";
}
for (i = 0; i < ARRAY_SIZE(commands); i++) {
struct cmd_struct *p = commands+i;
const char *prefix;
if (strcmp(p->cmd, cmd))
continue;
prefix = NULL;
if (p->option & RUN_SETUP)
prefix = setup_git_directory();
if (p->option & USE_PAGER)
setup_pager();
if ((p->option & NOT_BARE) &&
(is_bare_repository() || is_inside_git_dir()))
die("%s must be run in a work tree", cmd);
trace_argv_printf(argv, argc, "trace: built-in: git");
exit(p->fn(argc, argv, prefix));
}
}
int main(int argc, const char **argv, char **envp)
{
const char *cmd = argv[0] ? argv[0] : "git-help";
char *slash = strrchr(cmd, '/');
const char *exec_path = NULL;
int done_alias = 0;
/*
* Take the basename of argv[0] as the command
* name, and the dirname as the default exec_path
* if it's an absolute path and we don't have
* anything better.
*/
if (slash) {
*slash++ = 0;
if (*cmd == '/')
exec_path = cmd;
cmd = slash;
}
/*
* "git-xxxx" is the same as "git xxxx", but we obviously:
*
* - cannot take flags in between the "git" and the "xxxx".
* - cannot execute it externally (since it would just do
* the same thing over again)
*
* So we just directly call the internal command handler, and
* die if that one cannot handle it.
*/
if (!strncmp(cmd, "git-", 4)) {
cmd += 4;
argv[0] = cmd;
handle_internal_command(argc, argv, envp);
die("cannot handle %s internally", cmd);
}
/* Look for flags.. */
argv++;
argc--;
handle_options(&argv, &argc);
if (argc > 0) {
if (!strncmp(argv[0], "--", 2))
argv[0] += 2;
} else {
/* Default command: "help" */
argv[0] = "help";
argc = 1;
}
cmd = argv[0];
/*
* We search for git commands in the following order:
* - git_exec_path()
* - the path of the "git" command if we could find it
* in $0
* - the regular PATH.
*/
if (exec_path)
prepend_to_path(exec_path, strlen(exec_path));
exec_path = git_exec_path();
prepend_to_path(exec_path, strlen(exec_path));
while (1) {
/* See if it's an internal command */
handle_internal_command(argc, argv, envp);
/* .. then try the external ones */
execv_git_cmd(argv);
/* It could be an alias -- this works around the insanity
* of overriding "git log" with "git show" by having
* alias.log = show
*/
if (done_alias || !handle_alias(&argc, &argv))
break;
done_alias = 1;
}
if (errno == ENOENT) {
if (done_alias) {
fprintf(stderr, "Expansion of alias '%s' failed; "
"'%s' is not a git-command\n",
cmd, argv[0]);
exit(1);
}
help_unknown_cmd(cmd);
}
fprintf(stderr, "Failed to run command '%s': %s\n",
cmd, strerror(errno));
return 1;
}