Revision 3ebbd00cf3c5a7c6f90e2fed8adaf0c5145fb4ac authored by Jim Hill on 31 May 2015, 18:16:45 UTC, committed by Junio C Hamano on 10 August 2015, 19:51:13 UTC
The loop in strbuf_read() uses xread() repeatedly while extending the strbuf until the call returns zero. If the buffer is sufficiently large to begin with, this results in xread() returning the remainder of the file to the end (returning non-zero), the loop extending the strbuf, and then making another call to xread() to have it return zero. By using read_in_full(), we can tell when the read reached the end of file: when it returns less than was requested, it's eof. This way we can avoid an extra iteration that allocates an extra 8kB that is never used. Signed-off-by: Jim Hill <gjthill@gmail.com> Reviewed-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
1 parent 282616c
git.c
#include "builtin.h"
#include "cache.h"
#include "exec_cmd.h"
#include "help.h"
#include "quote.h"
#include "run-command.h"
#include "commit.h"
const char git_usage_string[] =
"git [--version] [--help] [-C <path>] [-c name=value]\n"
" [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
" [-p|--paginate|--no-pager] [--no-replace-objects] [--bare]\n"
" [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
" <command> [<args>]";
const char git_more_info_string[] =
N_("'git help -a' and 'git help -g' lists 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 void commit_pager_choice(void) {
switch (use_pager) {
case 0:
setenv("GIT_PAGER", "cat", 1);
break;
case 1:
setup_pager();
break;
default:
break;
}
}
static int handle_options(const char ***argv, int *argc, int *envchanged)
{
const char **orig_argv = *argv;
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 (starts_with(cmd, "--exec-path")) {
cmd += 11;
if (*cmd == '=')
git_set_argv_exec_path(cmd + 1);
else {
puts(git_exec_path());
exit(0);
}
} else if (!strcmp(cmd, "--html-path")) {
puts(system_path(GIT_HTML_PATH));
exit(0);
} else if (!strcmp(cmd, "--man-path")) {
puts(system_path(GIT_MAN_PATH));
exit(0);
} else if (!strcmp(cmd, "--info-path")) {
puts(system_path(GIT_INFO_PATH));
exit(0);
} else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
use_pager = 1;
} else if (!strcmp(cmd, "--no-pager")) {
use_pager = 0;
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--no-replace-objects")) {
check_replace_refs = 0;
setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
if (envchanged)
*envchanged = 1;
} 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);
if (envchanged)
*envchanged = 1;
(*argv)++;
(*argc)--;
} else if (starts_with(cmd, "--git-dir=")) {
setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--namespace")) {
if (*argc < 2) {
fprintf(stderr, "No namespace given for --namespace.\n" );
usage(git_usage_string);
}
setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
if (envchanged)
*envchanged = 1;
(*argv)++;
(*argc)--;
} else if (starts_with(cmd, "--namespace=")) {
setenv(GIT_NAMESPACE_ENVIRONMENT, cmd + 12, 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--work-tree")) {
if (*argc < 2) {
fprintf(stderr, "No directory given for --work-tree.\n" );
usage(git_usage_string);
}
setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
if (envchanged)
*envchanged = 1;
(*argv)++;
(*argc)--;
} else if (starts_with(cmd, "--work-tree=")) {
setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--bare")) {
static char git_dir[PATH_MAX+1];
is_bare_repository_cfg = 1;
setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "-c")) {
if (*argc < 2) {
fprintf(stderr, "-c expects a configuration string\n" );
usage(git_usage_string);
}
git_config_push_parameter((*argv)[1]);
(*argv)++;
(*argc)--;
} else if (!strcmp(cmd, "--literal-pathspecs")) {
setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--no-literal-pathspecs")) {
setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--glob-pathspecs")) {
setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--noglob-pathspecs")) {
setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--icase-pathspecs")) {
setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "--shallow-file")) {
(*argv)++;
(*argc)--;
set_alternate_shallow_file((*argv)[0], 1);
if (envchanged)
*envchanged = 1;
} else if (!strcmp(cmd, "-C")) {
if (*argc < 2) {
fprintf(stderr, "No directory given for -C.\n" );
usage(git_usage_string);
}
if (chdir((*argv)[1]))
die_errno("Cannot change to '%s'", (*argv)[1]);
if (envchanged)
*envchanged = 1;
(*argv)++;
(*argc)--;
} else {
fprintf(stderr, "Unknown option: %s\n", cmd);
usage(git_usage_string);
}
(*argv)++;
(*argc)--;
}
return (*argv) - orig_argv;
}
static int handle_alias(int *argcp, const char ***argv)
{
int envchanged = 0, ret = 0, saved_errno = errno;
const char *subdir;
int count, option_count;
const char **new_argv;
const char *alias_command;
char *alias_string;
int unused_nongit;
subdir = setup_git_directory_gently(&unused_nongit);
alias_command = (*argv)[0];
alias_string = alias_lookup(alias_command);
if (alias_string) {
if (alias_string[0] == '!') {
const char **alias_argv;
int argc = *argcp, i;
commit_pager_choice();
/* build alias_argv */
alias_argv = xmalloc(sizeof(*alias_argv) * (argc + 1));
alias_argv[0] = alias_string + 1;
for (i = 1; i < argc; ++i)
alias_argv[i] = (*argv)[i];
alias_argv[argc] = NULL;
ret = run_command_v_opt(alias_argv, RUN_USING_SHELL);
if (ret >= 0) /* normal exit */
exit(ret);
die_errno("While expanding alias '%s': '%s'",
alias_command, alias_string + 1);
}
count = split_cmdline(alias_string, &new_argv);
if (count < 0)
die("Bad alias.%s string: %s", alias_command,
split_cmdline_strerror(count));
option_count = handle_options(&new_argv, &count, &envchanged);
if (envchanged)
die("alias '%s' changes environment variables\n"
"You can use '!git' in the alias to do this.",
alias_command);
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,
"trace: alias expansion: %s =>",
alias_command);
new_argv = xrealloc(new_argv, sizeof(char *) *
(count + *argcp));
/* insert after command name */
memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
*argv = new_argv;
*argcp += count - 1;
ret = 1;
}
if (subdir && chdir(subdir))
die_errno("Cannot change to '%s'", subdir);
errno = saved_errno;
return ret;
}
#define RUN_SETUP (1<<0)
#define RUN_SETUP_GENTLY (1<<1)
#define USE_PAGER (1<<2)
/*
* require working tree to be present -- anything uses this needs
* RUN_SETUP for reading from the configuration file.
*/
#define NEED_WORK_TREE (1<<3)
struct cmd_struct {
const char *cmd;
int (*fn)(int, const char **, const char *);
int option;
};
static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
{
int status, help;
struct stat st;
const char *prefix;
prefix = NULL;
help = argc == 2 && !strcmp(argv[1], "-h");
if (!help) {
if (p->option & RUN_SETUP)
prefix = setup_git_directory();
if (p->option & RUN_SETUP_GENTLY) {
int nongit_ok;
prefix = setup_git_directory_gently(&nongit_ok);
}
if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
use_pager = check_pager_config(p->cmd);
if (use_pager == -1 && p->option & USE_PAGER)
use_pager = 1;
if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
trace_repo_setup(prefix);
}
commit_pager_choice();
if (!help && p->option & NEED_WORK_TREE)
setup_work_tree();
trace_argv_printf(argv, "trace: built-in: git");
status = p->fn(argc, argv, prefix);
if (status)
return status;
/* Somebody closed stdout? */
if (fstat(fileno(stdout), &st))
return 0;
/* Ignore write errors for pipes and sockets.. */
if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
return 0;
/* Check for ENOSPC and EIO errors.. */
if (fflush(stdout))
die_errno("write failure on standard output");
if (ferror(stdout))
die("unknown write failure on standard output");
if (fclose(stdout))
die_errno("close failed on standard output");
return 0;
}
static struct cmd_struct commands[] = {
{ "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
{ "annotate", cmd_annotate, RUN_SETUP },
{ "apply", cmd_apply, RUN_SETUP_GENTLY },
{ "archive", cmd_archive },
{ "bisect--helper", cmd_bisect__helper, RUN_SETUP },
{ "blame", cmd_blame, RUN_SETUP },
{ "branch", cmd_branch, RUN_SETUP },
{ "bundle", cmd_bundle, RUN_SETUP_GENTLY },
{ "cat-file", cmd_cat_file, RUN_SETUP },
{ "check-attr", cmd_check_attr, RUN_SETUP },
{ "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
{ "check-mailmap", cmd_check_mailmap, RUN_SETUP },
{ "check-ref-format", cmd_check_ref_format },
{ "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
{ "checkout-index", cmd_checkout_index,
RUN_SETUP | NEED_WORK_TREE},
{ "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 },
{ "column", cmd_column, RUN_SETUP_GENTLY },
{ "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
{ "commit-tree", cmd_commit_tree, RUN_SETUP },
{ "config", cmd_config, RUN_SETUP_GENTLY },
{ "count-objects", cmd_count_objects, RUN_SETUP },
{ "credential", cmd_credential, RUN_SETUP_GENTLY },
{ "describe", cmd_describe, RUN_SETUP },
{ "diff", cmd_diff },
{ "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
{ "diff-index", cmd_diff_index, RUN_SETUP },
{ "diff-tree", cmd_diff_tree, RUN_SETUP },
{ "fast-export", cmd_fast_export, RUN_SETUP },
{ "fetch", cmd_fetch, RUN_SETUP },
{ "fetch-pack", cmd_fetch_pack, 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 },
{ "gc", cmd_gc, RUN_SETUP },
{ "get-tar-commit-id", cmd_get_tar_commit_id },
{ "grep", cmd_grep, RUN_SETUP_GENTLY },
{ "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 },
{ "log", cmd_log, RUN_SETUP },
{ "ls-files", cmd_ls_files, RUN_SETUP },
{ "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
{ "ls-tree", cmd_ls_tree, RUN_SETUP },
{ "mailinfo", cmd_mailinfo },
{ "mailsplit", cmd_mailsplit },
{ "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
{ "merge-base", cmd_merge_base, RUN_SETUP },
{ "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
{ "merge-index", cmd_merge_index, RUN_SETUP },
{ "merge-ours", cmd_merge_ours, RUN_SETUP },
{ "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
{ "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
{ "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
{ "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
{ "merge-tree", cmd_merge_tree, RUN_SETUP },
{ "mktag", cmd_mktag, RUN_SETUP },
{ "mktree", cmd_mktree, RUN_SETUP },
{ "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
{ "name-rev", cmd_name_rev, RUN_SETUP },
{ "notes", cmd_notes, RUN_SETUP },
{ "pack-objects", cmd_pack_objects, RUN_SETUP },
{ "pack-redundant", cmd_pack_redundant, RUN_SETUP },
{ "pack-refs", cmd_pack_refs, RUN_SETUP },
{ "patch-id", cmd_patch_id },
{ "pickaxe", cmd_blame, RUN_SETUP },
{ "prune", cmd_prune, RUN_SETUP },
{ "prune-packed", cmd_prune_packed, RUN_SETUP },
{ "push", cmd_push, RUN_SETUP },
{ "read-tree", cmd_read_tree, RUN_SETUP },
{ "receive-pack", cmd_receive_pack },
{ "reflog", cmd_reflog, RUN_SETUP },
{ "remote", cmd_remote, RUN_SETUP },
{ "remote-ext", cmd_remote_ext },
{ "remote-fd", cmd_remote_fd },
{ "repack", cmd_repack, RUN_SETUP },
{ "replace", cmd_replace, RUN_SETUP },
{ "rerere", cmd_rerere, RUN_SETUP },
{ "reset", cmd_reset, RUN_SETUP },
{ "rev-list", cmd_rev_list, RUN_SETUP },
{ "rev-parse", cmd_rev_parse },
{ "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
{ "rm", cmd_rm, RUN_SETUP },
{ "send-pack", cmd_send_pack, RUN_SETUP },
{ "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
{ "show", cmd_show, RUN_SETUP },
{ "show-branch", cmd_show_branch, RUN_SETUP },
{ "show-ref", cmd_show_ref, RUN_SETUP },
{ "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
{ "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
{ "stripspace", cmd_stripspace },
{ "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
{ "tag", cmd_tag, RUN_SETUP },
{ "unpack-file", cmd_unpack_file, RUN_SETUP },
{ "unpack-objects", cmd_unpack_objects, RUN_SETUP },
{ "update-index", cmd_update_index, RUN_SETUP },
{ "update-ref", cmd_update_ref, RUN_SETUP },
{ "update-server-info", cmd_update_server_info, RUN_SETUP },
{ "upload-archive", cmd_upload_archive },
{ "upload-archive--writer", cmd_upload_archive_writer },
{ "var", cmd_var, RUN_SETUP_GENTLY },
{ "verify-pack", cmd_verify_pack },
{ "verify-tag", cmd_verify_tag, RUN_SETUP },
{ "version", cmd_version },
{ "whatchanged", cmd_whatchanged, RUN_SETUP },
{ "write-tree", cmd_write_tree, RUN_SETUP },
};
int is_builtin(const char *s)
{
int i;
for (i = 0; i < ARRAY_SIZE(commands); i++) {
struct cmd_struct *p = commands+i;
if (!strcmp(s, p->cmd))
return 1;
}
return 0;
}
static void handle_builtin(int argc, const char **argv)
{
const char *cmd = argv[0];
int i;
static const char ext[] = STRIP_EXTENSION;
if (sizeof(ext) > 1) {
i = strlen(argv[0]) - strlen(ext);
if (i > 0 && !strcmp(argv[0] + i, ext)) {
char *argv0 = xstrdup(argv[0]);
argv[0] = cmd = argv0;
argv0[i] = '\0';
}
}
/* 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;
if (strcmp(p->cmd, cmd))
continue;
exit(run_builtin(p, argc, argv));
}
}
static void execv_dashed_external(const char **argv)
{
struct strbuf cmd = STRBUF_INIT;
const char *tmp;
int status;
if (use_pager == -1)
use_pager = check_pager_config(argv[0]);
commit_pager_choice();
strbuf_addf(&cmd, "git-%s", argv[0]);
/*
* argv[0] must be the git command, but the argv array
* belongs to the caller, and may be reused in
* subsequent loop iterations. Save argv[0] and
* restore it on error.
*/
tmp = argv[0];
argv[0] = cmd.buf;
trace_argv_printf(argv, "trace: exec:");
/*
* if we fail because the command is not found, it is
* OK to return. Otherwise, we just pass along the status code.
*/
status = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE | RUN_CLEAN_ON_EXIT);
if (status >= 0 || errno != ENOENT)
exit(status);
argv[0] = tmp;
strbuf_release(&cmd);
}
static int run_argv(int *argcp, const char ***argv)
{
int done_alias = 0;
while (1) {
/* See if it's a builtin */
handle_builtin(*argcp, *argv);
/* .. then try the external ones */
execv_dashed_external(*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(argcp, argv))
break;
done_alias = 1;
}
return done_alias;
}
int main(int argc, char **av)
{
const char **argv = (const char **) av;
const char *cmd;
startup_info = &git_startup_info;
cmd = git_extract_argv0_path(argv[0]);
if (!cmd)
cmd = "git-help";
/*
* Always open file descriptors 0/1/2 to avoid clobbering files
* in die(). It also avoids messing up when the pipes are dup'ed
* onto stdin/stdout/stderr in the child processes we spawn.
*/
sanitize_stdfds();
git_setup_gettext();
/*
* "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 builtin handler, and die if
* that one cannot handle it.
*/
if (starts_with(cmd, "git-")) {
cmd += 4;
argv[0] = cmd;
handle_builtin(argc, argv);
die("cannot handle %s as a builtin", cmd);
}
/* Look for flags.. */
argv++;
argc--;
handle_options(&argv, &argc, NULL);
if (argc > 0) {
if (starts_with(argv[0], "--"))
argv[0] += 2;
} else {
/* The user didn't specify a command; give them help */
commit_pager_choice();
printf("usage: %s\n\n", git_usage_string);
list_common_cmds_help();
printf("\n%s\n", _(git_more_info_string));
exit(1);
}
cmd = argv[0];
/*
* We use PATH to find git commands, but we prepend some higher
* precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
* environment, and the $(gitexecdir) from the Makefile at build
* time.
*/
setup_path();
while (1) {
static int done_help = 0;
static int was_alias = 0;
was_alias = run_argv(&argc, &argv);
if (errno != ENOENT)
break;
if (was_alias) {
fprintf(stderr, "Expansion of alias '%s' failed; "
"'%s' is not a git command\n",
cmd, argv[0]);
exit(1);
}
if (!done_help) {
cmd = argv[0] = help_unknown_cmd(cmd);
done_help = 1;
} else
break;
}
fprintf(stderr, "Failed to run command '%s': %s\n",
cmd, strerror(errno));
return 1;
}
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