git/help.c
Teemu Likonen b7d9681974 Print info about "git help COMMAND" on git's main usage pages
Git's main usage pages did not show "git help" as a way to get more
information on a specific subcommand. This patch adds an info line after
the list of git commands currently printed by "git", "git help", "git
--help" and "git help --all".

Signed-off-by: Teemu Likonen <tlikonen@iki.fi>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-06-06 09:22:18 -07:00

683 lines
16 KiB
C

/*
* builtin-help.c
*
* Builtin help-related commands (help, usage, version)
*/
#include "cache.h"
#include "builtin.h"
#include "exec_cmd.h"
#include "common-cmds.h"
#include "parse-options.h"
#include "run-command.h"
static struct man_viewer_list {
struct man_viewer_list *next;
char name[FLEX_ARRAY];
} *man_viewer_list;
static struct man_viewer_info_list {
struct man_viewer_info_list *next;
const char *info;
char name[FLEX_ARRAY];
} *man_viewer_info_list;
enum help_format {
HELP_FORMAT_MAN,
HELP_FORMAT_INFO,
HELP_FORMAT_WEB,
};
static int show_all = 0;
static enum help_format help_format = HELP_FORMAT_MAN;
static struct option builtin_help_options[] = {
OPT_BOOLEAN('a', "all", &show_all, "print all available commands"),
OPT_SET_INT('m', "man", &help_format, "show man page", HELP_FORMAT_MAN),
OPT_SET_INT('w', "web", &help_format, "show manual in web browser",
HELP_FORMAT_WEB),
OPT_SET_INT('i', "info", &help_format, "show info page",
HELP_FORMAT_INFO),
OPT_END(),
};
static const char * const builtin_help_usage[] = {
"git-help [--all] [--man|--web|--info] [command]",
NULL
};
static enum help_format parse_help_format(const char *format)
{
if (!strcmp(format, "man"))
return HELP_FORMAT_MAN;
if (!strcmp(format, "info"))
return HELP_FORMAT_INFO;
if (!strcmp(format, "web") || !strcmp(format, "html"))
return HELP_FORMAT_WEB;
die("unrecognized help format '%s'", format);
}
static const char *get_man_viewer_info(const char *name)
{
struct man_viewer_info_list *viewer;
for (viewer = man_viewer_info_list; viewer; viewer = viewer->next)
{
if (!strcasecmp(name, viewer->name))
return viewer->info;
}
return NULL;
}
static int check_emacsclient_version(void)
{
struct strbuf buffer = STRBUF_INIT;
struct child_process ec_process;
const char *argv_ec[] = { "emacsclient", "--version", NULL };
int version;
/* emacsclient prints its version number on stderr */
memset(&ec_process, 0, sizeof(ec_process));
ec_process.argv = argv_ec;
ec_process.err = -1;
ec_process.stdout_to_stderr = 1;
if (start_command(&ec_process)) {
fprintf(stderr, "Failed to start emacsclient.\n");
return -1;
}
strbuf_read(&buffer, ec_process.err, 20);
close(ec_process.err);
/*
* Don't bother checking return value, because "emacsclient --version"
* seems to always exits with code 1.
*/
finish_command(&ec_process);
if (prefixcmp(buffer.buf, "emacsclient")) {
fprintf(stderr, "Failed to parse emacsclient version.\n");
strbuf_release(&buffer);
return -1;
}
strbuf_remove(&buffer, 0, strlen("emacsclient"));
version = atoi(buffer.buf);
if (version < 22) {
fprintf(stderr,
"emacsclient version '%d' too old (< 22).\n",
version);
strbuf_release(&buffer);
return -1;
}
strbuf_release(&buffer);
return 0;
}
static void exec_woman_emacs(const char* path, const char *page)
{
if (!check_emacsclient_version()) {
/* This works only with emacsclient version >= 22. */
struct strbuf man_page = STRBUF_INIT;
if (!path)
path = "emacsclient";
strbuf_addf(&man_page, "(woman \"%s\")", page);
execlp(path, "emacsclient", "-e", man_page.buf, NULL);
warning("failed to exec '%s': %s", path, strerror(errno));
}
}
static void exec_man_konqueror(const char* path, const char *page)
{
const char *display = getenv("DISPLAY");
if (display && *display) {
struct strbuf man_page = STRBUF_INIT;
const char *filename = "kfmclient";
/* It's simpler to launch konqueror using kfmclient. */
if (path) {
const char *file = strrchr(path, '/');
if (file && !strcmp(file + 1, "konqueror")) {
char *new = xstrdup(path);
char *dest = strrchr(new, '/');
/* strlen("konqueror") == strlen("kfmclient") */
strcpy(dest + 1, "kfmclient");
path = new;
}
if (file)
filename = file;
} else
path = "kfmclient";
strbuf_addf(&man_page, "man:%s(1)", page);
execlp(path, filename, "newTab", man_page.buf, NULL);
warning("failed to exec '%s': %s", path, strerror(errno));
}
}
static void exec_man_man(const char* path, const char *page)
{
if (!path)
path = "man";
execlp(path, "man", page, NULL);
warning("failed to exec '%s': %s", path, strerror(errno));
}
static void exec_man_cmd(const char *cmd, const char *page)
{
struct strbuf shell_cmd = STRBUF_INIT;
strbuf_addf(&shell_cmd, "%s %s", cmd, page);
execl("/bin/sh", "sh", "-c", shell_cmd.buf, NULL);
warning("failed to exec '%s': %s", cmd, strerror(errno));
}
static void add_man_viewer(const char *name)
{
struct man_viewer_list **p = &man_viewer_list;
size_t len = strlen(name);
while (*p)
p = &((*p)->next);
*p = xcalloc(1, (sizeof(**p) + len + 1));
strncpy((*p)->name, name, len);
}
static int supported_man_viewer(const char *name, size_t len)
{
return (!strncasecmp("man", name, len) ||
!strncasecmp("woman", name, len) ||
!strncasecmp("konqueror", name, len));
}
static void do_add_man_viewer_info(const char *name,
size_t len,
const char *value)
{
struct man_viewer_info_list *new = xcalloc(1, sizeof(*new) + len + 1);
strncpy(new->name, name, len);
new->info = xstrdup(value);
new->next = man_viewer_info_list;
man_viewer_info_list = new;
}
static int add_man_viewer_path(const char *name,
size_t len,
const char *value)
{
if (supported_man_viewer(name, len))
do_add_man_viewer_info(name, len, value);
else
warning("'%s': path for unsupported man viewer.\n"
"Please consider using 'man.<tool>.cmd' instead.",
name);
return 0;
}
static int add_man_viewer_cmd(const char *name,
size_t len,
const char *value)
{
if (supported_man_viewer(name, len))
warning("'%s': cmd for supported man viewer.\n"
"Please consider using 'man.<tool>.path' instead.",
name);
else
do_add_man_viewer_info(name, len, value);
return 0;
}
static int add_man_viewer_info(const char *var, const char *value)
{
const char *name = var + 4;
const char *subkey = strrchr(name, '.');
if (!subkey)
return error("Config with no key for man viewer: %s", name);
if (!strcmp(subkey, ".path")) {
if (!value)
return config_error_nonbool(var);
return add_man_viewer_path(name, subkey - name, value);
}
if (!strcmp(subkey, ".cmd")) {
if (!value)
return config_error_nonbool(var);
return add_man_viewer_cmd(name, subkey - name, value);
}
warning("'%s': unsupported man viewer sub key.", subkey);
return 0;
}
static int git_help_config(const char *var, const char *value, void *cb)
{
if (!strcmp(var, "help.format")) {
if (!value)
return config_error_nonbool(var);
help_format = parse_help_format(value);
return 0;
}
if (!strcmp(var, "man.viewer")) {
if (!value)
return config_error_nonbool(var);
add_man_viewer(value);
return 0;
}
if (!prefixcmp(var, "man."))
return add_man_viewer_info(var, value);
return git_default_config(var, value, cb);
}
/* most GUI terminals set COLUMNS (although some don't export it) */
static int term_columns(void)
{
char *col_string = getenv("COLUMNS");
int n_cols;
if (col_string && (n_cols = atoi(col_string)) > 0)
return n_cols;
#ifdef TIOCGWINSZ
{
struct winsize ws;
if (!ioctl(1, TIOCGWINSZ, &ws)) {
if (ws.ws_col)
return ws.ws_col;
}
}
#endif
return 80;
}
static inline void mput_char(char c, unsigned int num)
{
while(num--)
putchar(c);
}
static struct cmdnames {
int alloc;
int cnt;
struct cmdname {
size_t len;
char name[1];
} **names;
} main_cmds, other_cmds;
static void add_cmdname(struct cmdnames *cmds, const char *name, int len)
{
struct cmdname *ent = xmalloc(sizeof(*ent) + len);
ent->len = len;
memcpy(ent->name, name, len);
ent->name[len] = 0;
ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
cmds->names[cmds->cnt++] = ent;
}
static int cmdname_compare(const void *a_, const void *b_)
{
struct cmdname *a = *(struct cmdname **)a_;
struct cmdname *b = *(struct cmdname **)b_;
return strcmp(a->name, b->name);
}
static void uniq(struct cmdnames *cmds)
{
int i, j;
if (!cmds->cnt)
return;
for (i = j = 1; i < cmds->cnt; i++)
if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name))
cmds->names[j++] = cmds->names[i];
cmds->cnt = j;
}
static void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
{
int ci, cj, ei;
int cmp;
ci = cj = ei = 0;
while (ci < cmds->cnt && ei < excludes->cnt) {
cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
if (cmp < 0)
cmds->names[cj++] = cmds->names[ci++];
else if (cmp == 0)
ci++, ei++;
else if (cmp > 0)
ei++;
}
while (ci < cmds->cnt)
cmds->names[cj++] = cmds->names[ci++];
cmds->cnt = cj;
}
static void pretty_print_string_list(struct cmdnames *cmds, int longest)
{
int cols = 1, rows;
int space = longest + 1; /* min 1 SP between words */
int max_cols = term_columns() - 1; /* don't print *on* the edge */
int i, j;
if (space < max_cols)
cols = max_cols / space;
rows = (cmds->cnt + cols - 1) / cols;
for (i = 0; i < rows; i++) {
printf(" ");
for (j = 0; j < cols; j++) {
int n = j * rows + i;
int size = space;
if (n >= cmds->cnt)
break;
if (j == cols-1 || n + rows >= cmds->cnt)
size = 1;
printf("%-*s", size, cmds->names[n]->name);
}
putchar('\n');
}
}
static unsigned int list_commands_in_dir(struct cmdnames *cmds,
const char *path)
{
unsigned int longest = 0;
const char *prefix = "git-";
int prefix_len = strlen(prefix);
DIR *dir = opendir(path);
struct dirent *de;
if (!dir || chdir(path))
return 0;
while ((de = readdir(dir)) != NULL) {
struct stat st;
int entlen;
if (prefixcmp(de->d_name, prefix))
continue;
if (stat(de->d_name, &st) || /* stat, not lstat */
!S_ISREG(st.st_mode) ||
!(st.st_mode & S_IXUSR))
continue;
entlen = strlen(de->d_name) - prefix_len;
if (has_extension(de->d_name, ".exe"))
entlen -= 4;
if (longest < entlen)
longest = entlen;
add_cmdname(cmds, de->d_name + prefix_len, entlen);
}
closedir(dir);
return longest;
}
static unsigned int load_command_list(void)
{
unsigned int longest = 0;
unsigned int len;
const char *env_path = getenv("PATH");
char *paths, *path, *colon;
const char *exec_path = git_exec_path();
if (exec_path)
longest = list_commands_in_dir(&main_cmds, exec_path);
if (!env_path) {
fprintf(stderr, "PATH not set\n");
exit(1);
}
path = paths = xstrdup(env_path);
while (1) {
if ((colon = strchr(path, ':')))
*colon = 0;
len = list_commands_in_dir(&other_cmds, path);
if (len > longest)
longest = len;
if (!colon)
break;
path = colon + 1;
}
free(paths);
qsort(main_cmds.names, main_cmds.cnt,
sizeof(*main_cmds.names), cmdname_compare);
uniq(&main_cmds);
qsort(other_cmds.names, other_cmds.cnt,
sizeof(*other_cmds.names), cmdname_compare);
uniq(&other_cmds);
exclude_cmds(&other_cmds, &main_cmds);
return longest;
}
static void list_commands(void)
{
unsigned int longest = load_command_list();
const char *exec_path = git_exec_path();
if (main_cmds.cnt) {
printf("available git commands in '%s'\n", exec_path);
printf("----------------------------");
mput_char('-', strlen(exec_path));
putchar('\n');
pretty_print_string_list(&main_cmds, longest);
putchar('\n');
}
if (other_cmds.cnt) {
printf("git commands available from elsewhere on your $PATH\n");
printf("---------------------------------------------------\n");
pretty_print_string_list(&other_cmds, longest);
putchar('\n');
}
}
void list_common_cmds_help(void)
{
int i, longest = 0;
for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
if (longest < strlen(common_cmds[i].name))
longest = strlen(common_cmds[i].name);
}
puts("The most commonly used git commands are:");
for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
printf(" %s ", common_cmds[i].name);
mput_char(' ', longest - strlen(common_cmds[i].name));
puts(common_cmds[i].help);
}
}
static int is_in_cmdlist(struct cmdnames *c, const char *s)
{
int i;
for (i = 0; i < c->cnt; i++)
if (!strcmp(s, c->names[i]->name))
return 1;
return 0;
}
static int is_git_command(const char *s)
{
load_command_list();
return is_in_cmdlist(&main_cmds, s) ||
is_in_cmdlist(&other_cmds, s);
}
static const char *cmd_to_page(const char *git_cmd)
{
if (!git_cmd)
return "git";
else if (!prefixcmp(git_cmd, "git"))
return git_cmd;
else {
int page_len = strlen(git_cmd) + 4;
char *p = xmalloc(page_len + 1);
strcpy(p, "git-");
strcpy(p + 4, git_cmd);
p[page_len] = 0;
return p;
}
}
static void setup_man_path(void)
{
struct strbuf new_path;
const char *old_path = getenv("MANPATH");
strbuf_init(&new_path, 0);
/* We should always put ':' after our path. If there is no
* old_path, the ':' at the end will let 'man' to try
* system-wide paths after ours to find the manual page. If
* there is old_path, we need ':' as delimiter. */
strbuf_addstr(&new_path, GIT_MAN_PATH);
strbuf_addch(&new_path, ':');
if (old_path)
strbuf_addstr(&new_path, old_path);
setenv("MANPATH", new_path.buf, 1);
strbuf_release(&new_path);
}
static void exec_viewer(const char *name, const char *page)
{
const char *info = get_man_viewer_info(name);
if (!strcasecmp(name, "man"))
exec_man_man(info, page);
else if (!strcasecmp(name, "woman"))
exec_woman_emacs(info, page);
else if (!strcasecmp(name, "konqueror"))
exec_man_konqueror(info, page);
else if (info)
exec_man_cmd(info, page);
else
warning("'%s': unknown man viewer.", name);
}
static void show_man_page(const char *git_cmd)
{
struct man_viewer_list *viewer;
const char *page = cmd_to_page(git_cmd);
setup_man_path();
for (viewer = man_viewer_list; viewer; viewer = viewer->next)
{
exec_viewer(viewer->name, page); /* will return when unable */
}
exec_viewer("man", page);
die("no man viewer handled the request");
}
static void show_info_page(const char *git_cmd)
{
const char *page = cmd_to_page(git_cmd);
setenv("INFOPATH", GIT_INFO_PATH, 1);
execlp("info", "info", "gitman", page, NULL);
}
static void get_html_page_path(struct strbuf *page_path, const char *page)
{
struct stat st;
/* Check that we have a git documentation directory. */
if (stat(GIT_HTML_PATH "/git.html", &st) || !S_ISREG(st.st_mode))
die("'%s': not a documentation directory.", GIT_HTML_PATH);
strbuf_init(page_path, 0);
strbuf_addf(page_path, GIT_HTML_PATH "/%s.html", page);
}
static void show_html_page(const char *git_cmd)
{
const char *page = cmd_to_page(git_cmd);
struct strbuf page_path; /* it leaks but we exec bellow */
get_html_page_path(&page_path, page);
execl_git_cmd("web--browse", "-c", "help.browser", page_path.buf, NULL);
}
void help_unknown_cmd(const char *cmd)
{
fprintf(stderr, "git: '%s' is not a git-command. See 'git --help'.\n", cmd);
exit(1);
}
int cmd_version(int argc, const char **argv, const char *prefix)
{
printf("git version %s\n", git_version_string);
return 0;
}
int cmd_help(int argc, const char **argv, const char *prefix)
{
int nongit;
const char *alias;
setup_git_directory_gently(&nongit);
git_config(git_help_config, NULL);
argc = parse_options(argc, argv, builtin_help_options,
builtin_help_usage, 0);
if (show_all) {
printf("usage: %s\n\n", git_usage_string);
list_commands();
printf("%s\n", git_more_info_string);
return 0;
}
if (!argv[0]) {
printf("usage: %s\n\n", git_usage_string);
list_common_cmds_help();
printf("\n%s\n", git_more_info_string);
return 0;
}
alias = alias_lookup(argv[0]);
if (alias && !is_git_command(argv[0])) {
printf("`git %s' is aliased to `%s'\n", argv[0], alias);
return 0;
}
switch (help_format) {
case HELP_FORMAT_MAN:
show_man_page(argv[0]);
break;
case HELP_FORMAT_INFO:
show_info_page(argv[0]);
break;
case HELP_FORMAT_WEB:
show_html_page(argv[0]);
break;
}
return 0;
}