Andrew's git / gitweb.git / builtin/help.c
?
builtin / help.con commit subtree test: add missing && to &&-chain (ad6eee3)
   1/*
   2 * Builtin help command
   3 */
   4#include "cache.h"
   5#include "config.h"
   6#include "builtin.h"
   7#include "exec-cmd.h"
   8#include "parse-options.h"
   9#include "run-command.h"
  10#include "column.h"
  11#include "help.h"
  12#include "alias.h"
  13
  14#ifndef DEFAULT_HELP_FORMAT
  15#define DEFAULT_HELP_FORMAT "man"
  16#endif
  17
  18static struct man_viewer_list {
  19        struct man_viewer_list *next;
  20        char name[FLEX_ARRAY];
  21} *man_viewer_list;
  22
  23static struct man_viewer_info_list {
  24        struct man_viewer_info_list *next;
  25        const char *info;
  26        char name[FLEX_ARRAY];
  27} *man_viewer_info_list;
  28
  29enum help_format {
  30        HELP_FORMAT_NONE,
  31        HELP_FORMAT_MAN,
  32        HELP_FORMAT_INFO,
  33        HELP_FORMAT_WEB
  34};
  35
  36static const char *html_path;
  37
  38static int show_all = 0;
  39static int show_guides = 0;
  40static int verbose;
  41static unsigned int colopts;
  42static enum help_format help_format = HELP_FORMAT_NONE;
  43static int exclude_guides;
  44static struct option builtin_help_options[] = {
  45        OPT_BOOL('a', "all", &show_all, N_("print all available commands")),
  46        OPT_HIDDEN_BOOL(0, "exclude-guides", &exclude_guides, N_("exclude guides")),
  47        OPT_BOOL('g', "guides", &show_guides, N_("print list of useful guides")),
  48        OPT_SET_INT('m', "man", &help_format, N_("show man page"), HELP_FORMAT_MAN),
  49        OPT_SET_INT('w', "web", &help_format, N_("show manual in web browser"),
  50                        HELP_FORMAT_WEB),
  51        OPT_SET_INT('i', "info", &help_format, N_("show info page"),
  52                        HELP_FORMAT_INFO),
  53        OPT__VERBOSE(&verbose, N_("print command description")),
  54        OPT_END(),
  55};
  56
  57static const char * const builtin_help_usage[] = {
  58        N_("git help [--all] [--guides] [--man | --web | --info] [<command>]"),
  59        NULL
  60};
  61
  62static enum help_format parse_help_format(const char *format)
  63{
  64        if (!strcmp(format, "man"))
  65                return HELP_FORMAT_MAN;
  66        if (!strcmp(format, "info"))
  67                return HELP_FORMAT_INFO;
  68        if (!strcmp(format, "web") || !strcmp(format, "html"))
  69                return HELP_FORMAT_WEB;
  70        die(_("unrecognized help format '%s'"), format);
  71}
  72
  73static const char *get_man_viewer_info(const char *name)
  74{
  75        struct man_viewer_info_list *viewer;
  76
  77        for (viewer = man_viewer_info_list; viewer; viewer = viewer->next)
  78        {
  79                if (!strcasecmp(name, viewer->name))
  80                        return viewer->info;
  81        }
  82        return NULL;
  83}
  84
  85static int check_emacsclient_version(void)
  86{
  87        struct strbuf buffer = STRBUF_INIT;
  88        struct child_process ec_process = CHILD_PROCESS_INIT;
  89        const char *argv_ec[] = { "emacsclient", "--version", NULL };
  90        int version;
  91
  92        /* emacsclient prints its version number on stderr */
  93        ec_process.argv = argv_ec;
  94        ec_process.err = -1;
  95        ec_process.stdout_to_stderr = 1;
  96        if (start_command(&ec_process))
  97                return error(_("Failed to start emacsclient."));
  98
  99        strbuf_read(&buffer, ec_process.err, 20);
 100        close(ec_process.err);
 101
 102        /*
 103         * Don't bother checking return value, because "emacsclient --version"
 104         * seems to always exits with code 1.
 105         */
 106        finish_command(&ec_process);
 107
 108        if (!starts_with(buffer.buf, "emacsclient")) {
 109                strbuf_release(&buffer);
 110                return error(_("Failed to parse emacsclient version."));
 111        }
 112
 113        strbuf_remove(&buffer, 0, strlen("emacsclient"));
 114        version = atoi(buffer.buf);
 115
 116        if (version < 22) {
 117                strbuf_release(&buffer);
 118                return error(_("emacsclient version '%d' too old (< 22)."),
 119                        version);
 120        }
 121
 122        strbuf_release(&buffer);
 123        return 0;
 124}
 125
 126static void exec_woman_emacs(const char *path, const char *page)
 127{
 128        if (!check_emacsclient_version()) {
 129                /* This works only with emacsclient version >= 22. */
 130                struct strbuf man_page = STRBUF_INIT;
 131
 132                if (!path)
 133                        path = "emacsclient";
 134                strbuf_addf(&man_page, "(woman \"%s\")", page);
 135                execlp(path, "emacsclient", "-e", man_page.buf, (char *)NULL);
 136                warning_errno(_("failed to exec '%s'"), path);
 137                strbuf_release(&man_page);
 138        }
 139}
 140
 141static void exec_man_konqueror(const char *path, const char *page)
 142{
 143        const char *display = getenv("DISPLAY");
 144        if (display && *display) {
 145                struct strbuf man_page = STRBUF_INIT;
 146                const char *filename = "kfmclient";
 147
 148                /* It's simpler to launch konqueror using kfmclient. */
 149                if (path) {
 150                        size_t len;
 151                        if (strip_suffix(path, "/konqueror", &len))
 152                                path = xstrfmt("%.*s/kfmclient", (int)len, path);
 153                        filename = basename((char *)path);
 154                } else
 155                        path = "kfmclient";
 156                strbuf_addf(&man_page, "man:%s(1)", page);
 157                execlp(path, filename, "newTab", man_page.buf, (char *)NULL);
 158                warning_errno(_("failed to exec '%s'"), path);
 159                strbuf_release(&man_page);
 160        }
 161}
 162
 163static void exec_man_man(const char *path, const char *page)
 164{
 165        if (!path)
 166                path = "man";
 167        execlp(path, "man", page, (char *)NULL);
 168        warning_errno(_("failed to exec '%s'"), path);
 169}
 170
 171static void exec_man_cmd(const char *cmd, const char *page)
 172{
 173        struct strbuf shell_cmd = STRBUF_INIT;
 174        strbuf_addf(&shell_cmd, "%s %s", cmd, page);
 175        execl(SHELL_PATH, SHELL_PATH, "-c", shell_cmd.buf, (char *)NULL);
 176        warning(_("failed to exec '%s'"), cmd);
 177        strbuf_release(&shell_cmd);
 178}
 179
 180static void add_man_viewer(const char *name)
 181{
 182        struct man_viewer_list **p = &man_viewer_list;
 183
 184        while (*p)
 185                p = &((*p)->next);
 186        FLEX_ALLOC_STR(*p, name, name);
 187}
 188
 189static int supported_man_viewer(const char *name, size_t len)
 190{
 191        return (!strncasecmp("man", name, len) ||
 192                !strncasecmp("woman", name, len) ||
 193                !strncasecmp("konqueror", name, len));
 194}
 195
 196static void do_add_man_viewer_info(const char *name,
 197                                   size_t len,
 198                                   const char *value)
 199{
 200        struct man_viewer_info_list *new_man_viewer;
 201        FLEX_ALLOC_MEM(new_man_viewer, name, name, len);
 202        new_man_viewer->info = xstrdup(value);
 203        new_man_viewer->next = man_viewer_info_list;
 204        man_viewer_info_list = new_man_viewer;
 205}
 206
 207static int add_man_viewer_path(const char *name,
 208                               size_t len,
 209                               const char *value)
 210{
 211        if (supported_man_viewer(name, len))
 212                do_add_man_viewer_info(name, len, value);
 213        else
 214                warning(_("'%s': path for unsupported man viewer.\n"
 215                          "Please consider using 'man.<tool>.cmd' instead."),
 216                        name);
 217
 218        return 0;
 219}
 220
 221static int add_man_viewer_cmd(const char *name,
 222                              size_t len,
 223                              const char *value)
 224{
 225        if (supported_man_viewer(name, len))
 226                warning(_("'%s': cmd for supported man viewer.\n"
 227                          "Please consider using 'man.<tool>.path' instead."),
 228                        name);
 229        else
 230                do_add_man_viewer_info(name, len, value);
 231
 232        return 0;
 233}
 234
 235static int add_man_viewer_info(const char *var, const char *value)
 236{
 237        const char *name, *subkey;
 238        int namelen;
 239
 240        if (parse_config_key(var, "man", &name, &namelen, &subkey) < 0 || !name)
 241                return 0;
 242
 243        if (!strcmp(subkey, "path")) {
 244                if (!value)
 245                        return config_error_nonbool(var);
 246                return add_man_viewer_path(name, namelen, value);
 247        }
 248        if (!strcmp(subkey, "cmd")) {
 249                if (!value)
 250                        return config_error_nonbool(var);
 251                return add_man_viewer_cmd(name, namelen, value);
 252        }
 253
 254        return 0;
 255}
 256
 257static int git_help_config(const char *var, const char *value, void *cb)
 258{
 259        if (starts_with(var, "column."))
 260                return git_column_config(var, value, "help", &colopts);
 261        if (!strcmp(var, "help.format")) {
 262                if (!value)
 263                        return config_error_nonbool(var);
 264                help_format = parse_help_format(value);
 265                return 0;
 266        }
 267        if (!strcmp(var, "help.htmlpath")) {
 268                if (!value)
 269                        return config_error_nonbool(var);
 270                html_path = xstrdup(value);
 271                return 0;
 272        }
 273        if (!strcmp(var, "man.viewer")) {
 274                if (!value)
 275                        return config_error_nonbool(var);
 276                add_man_viewer(value);
 277                return 0;
 278        }
 279        if (starts_with(var, "man."))
 280                return add_man_viewer_info(var, value);
 281
 282        return git_default_config(var, value, cb);
 283}
 284
 285static struct cmdnames main_cmds, other_cmds;
 286
 287static int is_git_command(const char *s)
 288{
 289        if (is_builtin(s))
 290                return 1;
 291
 292        load_command_list("git-", &main_cmds, &other_cmds);
 293        return is_in_cmdlist(&main_cmds, s) ||
 294                is_in_cmdlist(&other_cmds, s);
 295}
 296
 297static const char *cmd_to_page(const char *git_cmd)
 298{
 299        if (!git_cmd)
 300                return "git";
 301        else if (starts_with(git_cmd, "git"))
 302                return git_cmd;
 303        else if (is_git_command(git_cmd))
 304                return xstrfmt("git-%s", git_cmd);
 305        else
 306                return xstrfmt("git%s", git_cmd);
 307}
 308
 309static void setup_man_path(void)
 310{
 311        struct strbuf new_path = STRBUF_INIT;
 312        const char *old_path = getenv("MANPATH");
 313        char *git_man_path = system_path(GIT_MAN_PATH);
 314
 315        /* We should always put ':' after our path. If there is no
 316         * old_path, the ':' at the end will let 'man' to try
 317         * system-wide paths after ours to find the manual page. If
 318         * there is old_path, we need ':' as delimiter. */
 319        strbuf_addstr(&new_path, git_man_path);
 320        strbuf_addch(&new_path, ':');
 321        if (old_path)
 322                strbuf_addstr(&new_path, old_path);
 323
 324        free(git_man_path);
 325        setenv("MANPATH", new_path.buf, 1);
 326
 327        strbuf_release(&new_path);
 328}
 329
 330static void exec_viewer(const char *name, const char *page)
 331{
 332        const char *info = get_man_viewer_info(name);
 333
 334        if (!strcasecmp(name, "man"))
 335                exec_man_man(info, page);
 336        else if (!strcasecmp(name, "woman"))
 337                exec_woman_emacs(info, page);
 338        else if (!strcasecmp(name, "konqueror"))
 339                exec_man_konqueror(info, page);
 340        else if (info)
 341                exec_man_cmd(info, page);
 342        else
 343                warning(_("'%s': unknown man viewer."), name);
 344}
 345
 346static void show_man_page(const char *git_cmd)
 347{
 348        struct man_viewer_list *viewer;
 349        const char *page = cmd_to_page(git_cmd);
 350        const char *fallback = getenv("GIT_MAN_VIEWER");
 351
 352        setup_man_path();
 353        for (viewer = man_viewer_list; viewer; viewer = viewer->next)
 354        {
 355                exec_viewer(viewer->name, page); /* will return when unable */
 356        }
 357        if (fallback)
 358                exec_viewer(fallback, page);
 359        exec_viewer("man", page);
 360        die(_("no man viewer handled the request"));
 361}
 362
 363static void show_info_page(const char *git_cmd)
 364{
 365        const char *page = cmd_to_page(git_cmd);
 366        setenv("INFOPATH", system_path(GIT_INFO_PATH), 1);
 367        execlp("info", "info", "gitman", page, (char *)NULL);
 368        die(_("no info viewer handled the request"));
 369}
 370
 371static void get_html_page_path(struct strbuf *page_path, const char *page)
 372{
 373        struct stat st;
 374        char *to_free = NULL;
 375
 376        if (!html_path)
 377                html_path = to_free = system_path(GIT_HTML_PATH);
 378
 379        /* Check that we have a git documentation directory. */
 380        if (!strstr(html_path, "://")) {
 381                if (stat(mkpath("%s/git.html", html_path), &st)
 382                    || !S_ISREG(st.st_mode))
 383                        die("'%s': not a documentation directory.", html_path);
 384        }
 385
 386        strbuf_init(page_path, 0);
 387        strbuf_addf(page_path, "%s/%s.html", html_path, page);
 388        free(to_free);
 389}
 390
 391static void open_html(const char *path)
 392{
 393        execl_git_cmd("web--browse", "-c", "help.browser", path, (char *)NULL);
 394}
 395
 396static void show_html_page(const char *git_cmd)
 397{
 398        const char *page = cmd_to_page(git_cmd);
 399        struct strbuf page_path; /* it leaks but we exec bellow */
 400
 401        get_html_page_path(&page_path, page);
 402
 403        open_html(page_path.buf);
 404}
 405
 406static const char *check_git_cmd(const char* cmd)
 407{
 408        char *alias;
 409
 410        if (is_git_command(cmd))
 411                return cmd;
 412
 413        alias = alias_lookup(cmd);
 414        if (alias) {
 415                printf_ln(_("'%s' is aliased to '%s'"), cmd, alias);
 416                free(alias);
 417                exit(0);
 418        }
 419
 420        if (exclude_guides)
 421                return help_unknown_cmd(cmd);
 422
 423        return cmd;
 424}
 425
 426int cmd_help(int argc, const char **argv, const char *prefix)
 427{
 428        int nongit;
 429        enum help_format parsed_help_format;
 430
 431        argc = parse_options(argc, argv, prefix, builtin_help_options,
 432                        builtin_help_usage, 0);
 433        parsed_help_format = help_format;
 434
 435        if (show_all) {
 436                git_config(git_help_config, NULL);
 437                if (verbose) {
 438                        setup_pager();
 439                        list_all_cmds_help();
 440                        return 0;
 441                }
 442                printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
 443                load_command_list("git-", &main_cmds, &other_cmds);
 444                list_commands(colopts, &main_cmds, &other_cmds);
 445        }
 446
 447        if (show_guides)
 448                list_common_guides_help();
 449
 450        if (show_all || show_guides) {
 451                printf("%s\n", _(git_more_info_string));
 452                /*
 453                * We're done. Ignore any remaining args
 454                */
 455                return 0;
 456        }
 457
 458        if (!argv[0]) {
 459                printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
 460                list_common_cmds_help();
 461                printf("\n%s\n", _(git_more_info_string));
 462                return 0;
 463        }
 464
 465        setup_git_directory_gently(&nongit);
 466        git_config(git_help_config, NULL);
 467
 468        if (parsed_help_format != HELP_FORMAT_NONE)
 469                help_format = parsed_help_format;
 470        if (help_format == HELP_FORMAT_NONE)
 471                help_format = parse_help_format(DEFAULT_HELP_FORMAT);
 472
 473        argv[0] = check_git_cmd(argv[0]);
 474
 475        switch (help_format) {
 476        case HELP_FORMAT_NONE:
 477        case HELP_FORMAT_MAN:
 478                show_man_page(argv[0]);
 479                break;
 480        case HELP_FORMAT_INFO:
 481                show_info_page(argv[0]);
 482                break;
 483        case HELP_FORMAT_WEB:
 484                show_html_page(argv[0]);
 485                break;
 486        }
 487
 488        return 0;
 489}