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-rw-r--r--builtin/help.c466
1 files changed, 466 insertions, 0 deletions
diff --git a/builtin/help.c b/builtin/help.c
new file mode 100644
index 0000000..3182a2b
--- /dev/null
+++ b/builtin/help.c
@@ -0,0 +1,466 @@
+/*
+ * builtin-help.c
+ *
+ * Builtin help command
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "exec_cmd.h"
+#include "common-cmds.h"
+#include "parse-options.h"
+#include "run-command.h"
+#include "help.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_NONE,
+ HELP_FORMAT_MAN,
+ HELP_FORMAT_INFO,
+ HELP_FORMAT_WEB,
+};
+
+static int show_all = 0;
+static enum help_format help_format = HELP_FORMAT_NONE;
+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))
+ return error("Failed to start emacsclient.");
+
+ 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")) {
+ strbuf_release(&buffer);
+ return error("Failed to parse emacsclient version.");
+ }
+
+ strbuf_remove(&buffer, 0, strlen("emacsclient"));
+ version = atoi(buffer.buf);
+
+ if (version < 22) {
+ strbuf_release(&buffer);
+ return error("emacsclient version '%d' too old (< 22).",
+ version);
+ }
+
+ 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 0;
+
+ 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);
+ }
+
+ 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);
+}
+
+static struct cmdnames main_cmds, other_cmds;
+
+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_git_command(const char *s)
+{
+ return is_in_cmdlist(&main_cmds, s) ||
+ is_in_cmdlist(&other_cmds, s);
+}
+
+static const char *prepend(const char *prefix, const char *cmd)
+{
+ size_t pre_len = strlen(prefix);
+ size_t cmd_len = strlen(cmd);
+ char *p = xmalloc(pre_len + cmd_len + 1);
+ memcpy(p, prefix, pre_len);
+ strcpy(p + pre_len, cmd);
+ return p;
+}
+
+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 if (is_git_command(git_cmd))
+ return prepend("git-", git_cmd);
+ else
+ return prepend("git", git_cmd);
+}
+
+static void setup_man_path(void)
+{
+ struct strbuf new_path = STRBUF_INIT;
+ const char *old_path = getenv("MANPATH");
+
+ /* 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, system_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);
+ const char *fallback = getenv("GIT_MAN_VIEWER");
+
+ setup_man_path();
+ for (viewer = man_viewer_list; viewer; viewer = viewer->next)
+ {
+ exec_viewer(viewer->name, page); /* will return when unable */
+ }
+ if (fallback)
+ exec_viewer(fallback, page);
+ 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", system_path(GIT_INFO_PATH), 1);
+ execlp("info", "info", "gitman", page, NULL);
+ die("no info viewer handled the request");
+}
+
+static void get_html_page_path(struct strbuf *page_path, const char *page)
+{
+ struct stat st;
+ const char *html_path = system_path(GIT_HTML_PATH);
+
+ /* Check that we have a git documentation directory. */
+ if (stat(mkpath("%s/git.html", html_path), &st)
+ || !S_ISREG(st.st_mode))
+ die("'%s': not a documentation directory.", html_path);
+
+ strbuf_init(page_path, 0);
+ strbuf_addf(page_path, "%s/%s.html", html_path, page);
+}
+
+/*
+ * If open_html is not defined in a platform-specific way (see for
+ * example compat/mingw.h), we use the script web--browse to display
+ * HTML.
+ */
+#ifndef open_html
+static void open_html(const char *path)
+{
+ execl_git_cmd("web--browse", "-c", "help.browser", path, NULL);
+}
+#endif
+
+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);
+
+ open_html(page_path.buf);
+}
+
+int cmd_help(int argc, const char **argv, const char *prefix)
+{
+ int nongit;
+ const char *alias;
+ enum help_format parsed_help_format;
+ load_command_list("git-", &main_cmds, &other_cmds);
+
+ argc = parse_options(argc, argv, prefix, builtin_help_options,
+ builtin_help_usage, 0);
+ parsed_help_format = help_format;
+
+ if (show_all) {
+ printf("usage: %s\n\n", git_usage_string);
+ list_commands("git commands", &main_cmds, &other_cmds);
+ 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;
+ }
+
+ setup_git_directory_gently(&nongit);
+ git_config(git_help_config, NULL);
+
+ if (parsed_help_format != HELP_FORMAT_NONE)
+ help_format = parsed_help_format;
+
+ 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_NONE:
+ 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;
+}