Andrew's git - gitweb.git/blob

12fb48933e7529207c953890902236b3217dfac9
   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
  13#ifndef DEFAULT_HELP_FORMAT
  14#define DEFAULT_HELP_FORMAT "man"
  15#endif
  16
  17static struct man_viewer_list {
  18        struct man_viewer_list *next;
  19        char name[FLEX_ARRAY];
  20} *man_viewer_list;
  21
  22static struct man_viewer_info_list {
  23        struct man_viewer_info_list *next;
  24        const char *info;
  25        char name[FLEX_ARRAY];
  26} *man_viewer_info_list;
  27
  28enum help_format {
  29        HELP_FORMAT_NONE,
  30        HELP_FORMAT_MAN,
  31        HELP_FORMAT_INFO,
  32        HELP_FORMAT_WEB
  33};
  34
  35static const char *html_path;
  36
  37static int show_all = 0;
  38static int show_guides = 0;
  39static unsigned int colopts;
  40static enum help_format help_format = HELP_FORMAT_NONE;
  41static int exclude_guides;
  42static struct option builtin_help_options[] = {
  43        OPT_BOOL('a', "all", &show_all, N_("print all available commands")),
  44        OPT_HIDDEN_BOOL(0, "exclude-guides", &exclude_guides, N_("exclude guides")),
  45        OPT_BOOL('g', "guides", &show_guides, N_("print list of useful guides")),
  46        OPT_SET_INT('m', "man", &help_format, N_("show man page"), HELP_FORMAT_MAN),
  47        OPT_SET_INT('w', "web", &help_format, N_("show manual in web browser"),
  48                        HELP_FORMAT_WEB),
  49        OPT_SET_INT('i', "info", &help_format, N_("show info page"),
  50                        HELP_FORMAT_INFO),
  51        OPT_END(),
  52};
  53
  54static const char * const builtin_help_usage[] = {
  55        N_("git help [--all] [--guides] [--man | --web | --info] [<command>]"),
  56        NULL
  57};
  58
  59static enum help_format parse_help_format(const char *format)
  60{
  61        if (!strcmp(format, "man"))
  62                return HELP_FORMAT_MAN;
  63        if (!strcmp(format, "info"))
  64                return HELP_FORMAT_INFO;
  65        if (!strcmp(format, "web") || !strcmp(format, "html"))
  66                return HELP_FORMAT_WEB;
  67        die(_("unrecognized help format '%s'"), format);
  68}
  69
  70static const char *get_man_viewer_info(const char *name)
  71{
  72        struct man_viewer_info_list *viewer;
  73
  74        for (viewer = man_viewer_info_list; viewer; viewer = viewer->next)
  75        {
  76                if (!strcasecmp(name, viewer->name))
  77                        return viewer->info;
  78        }
  79        return NULL;
  80}
  81
  82static int check_emacsclient_version(void)
  83{
  84        struct strbuf buffer = STRBUF_INIT;
  85        struct child_process ec_process = CHILD_PROCESS_INIT;
  86        const char *argv_ec[] = { "emacsclient", "--version", NULL };
  87        int version;
  88
  89        /* emacsclient prints its version number on stderr */
  90        ec_process.argv = argv_ec;
  91        ec_process.err = -1;
  92        ec_process.stdout_to_stderr = 1;
  93        if (start_command(&ec_process))
  94                return error(_("Failed to start emacsclient."));
  95
  96        strbuf_read(&buffer, ec_process.err, 20);
  97        close(ec_process.err);
  98
  99        /*
 100         * Don't bother checking return value, because "emacsclient --version"
 101         * seems to always exits with code 1.
 102         */
 103        finish_command(&ec_process);
 104
 105        if (!starts_with(buffer.buf, "emacsclient")) {
 106                strbuf_release(&buffer);
 107                return error(_("Failed to parse emacsclient version."));
 108        }
 109
 110        strbuf_remove(&buffer, 0, strlen("emacsclient"));
 111        version = atoi(buffer.buf);
 112
 113        if (version < 22) {
 114                strbuf_release(&buffer);
 115                return error(_("emacsclient version '%d' too old (< 22)."),
 116                        version);
 117        }
 118
 119        strbuf_release(&buffer);
 120        return 0;
 121}
 122
 123static void exec_woman_emacs(const char *path, const char *page)
 124{
 125        if (!check_emacsclient_version()) {
 126                /* This works only with emacsclient version >= 22. */
 127                struct strbuf man_page = STRBUF_INIT;
 128
 129                if (!path)
 130                        path = "emacsclient";
 131                strbuf_addf(&man_page, "(woman \"%s\")", page);
 132                execlp(path, "emacsclient", "-e", man_page.buf, (char *)NULL);
 133                warning_errno(_("failed to exec '%s'"), path);
 134        }
 135}
 136
 137static void exec_man_konqueror(const char *path, const char *page)
 138{
 139        const char *display = getenv("DISPLAY");
 140        if (display && *display) {
 141                struct strbuf man_page = STRBUF_INIT;
 142                const char *filename = "kfmclient";
 143
 144                /* It's simpler to launch konqueror using kfmclient. */
 145                if (path) {
 146                        size_t len;
 147                        if (strip_suffix(path, "/konqueror", &len))
 148                                path = xstrfmt("%.*s/kfmclient", (int)len, path);
 149                        filename = basename((char *)path);
 150                } else
 151                        path = "kfmclient";
 152                strbuf_addf(&man_page, "man:%s(1)", page);
 153                execlp(path, filename, "newTab", man_page.buf, (char *)NULL);
 154                warning_errno(_("failed to exec '%s'"), path);
 155                strbuf_release(&man_page);
 156        }
 157}
 158
 159static void exec_man_man(const char *path, const char *page)
 160{
 161        if (!path)
 162                path = "man";
 163        execlp(path, "man", page, (char *)NULL);
 164        warning_errno(_("failed to exec '%s'"), path);
 165}
 166
 167static void exec_man_cmd(const char *cmd, const char *page)
 168{
 169        struct strbuf shell_cmd = STRBUF_INIT;
 170        strbuf_addf(&shell_cmd, "%s %s", cmd, page);
 171        execl(SHELL_PATH, SHELL_PATH, "-c", shell_cmd.buf, (char *)NULL);
 172        warning(_("failed to exec '%s'"), cmd);
 173        strbuf_release(&shell_cmd);
 174}
 175
 176static void add_man_viewer(const char *name)
 177{
 178        struct man_viewer_list **p = &man_viewer_list;
 179
 180        while (*p)
 181                p = &((*p)->next);
 182        FLEX_ALLOC_STR(*p, name, name);
 183}
 184
 185static int supported_man_viewer(const char *name, size_t len)
 186{
 187        return (!strncasecmp("man", name, len) ||
 188                !strncasecmp("woman", name, len) ||
 189                !strncasecmp("konqueror", name, len));
 190}
 191
 192static void do_add_man_viewer_info(const char *name,
 193                                   size_t len,
 194                                   const char *value)
 195{
 196        struct man_viewer_info_list *new;
 197        FLEX_ALLOC_MEM(new, name, name, len);
 198        new->info = xstrdup(value);
 199        new->next = man_viewer_info_list;
 200        man_viewer_info_list = new;
 201}
 202
 203static int add_man_viewer_path(const char *name,
 204                               size_t len,
 205                               const char *value)
 206{
 207        if (supported_man_viewer(name, len))
 208                do_add_man_viewer_info(name, len, value);
 209        else
 210                warning(_("'%s': path for unsupported man viewer.\n"
 211                          "Please consider using 'man.<tool>.cmd' instead."),
 212                        name);
 213
 214        return 0;
 215}
 216
 217static int add_man_viewer_cmd(const char *name,
 218                              size_t len,
 219                              const char *value)
 220{
 221        if (supported_man_viewer(name, len))
 222                warning(_("'%s': cmd for supported man viewer.\n"
 223                          "Please consider using 'man.<tool>.path' instead."),
 224                        name);
 225        else
 226                do_add_man_viewer_info(name, len, value);
 227
 228        return 0;
 229}
 230
 231static int add_man_viewer_info(const char *var, const char *value)
 232{
 233        const char *name, *subkey;
 234        int namelen;
 235
 236        if (parse_config_key(var, "man", &name, &namelen, &subkey) < 0 || !name)
 237                return 0;
 238
 239        if (!strcmp(subkey, "path")) {
 240                if (!value)
 241                        return config_error_nonbool(var);
 242                return add_man_viewer_path(name, namelen, value);
 243        }
 244        if (!strcmp(subkey, "cmd")) {
 245                if (!value)
 246                        return config_error_nonbool(var);
 247                return add_man_viewer_cmd(name, namelen, value);
 248        }
 249
 250        return 0;
 251}
 252
 253static int git_help_config(const char *var, const char *value, void *cb)
 254{
 255        if (starts_with(var, "column."))
 256                return git_column_config(var, value, "help", &colopts);
 257        if (!strcmp(var, "help.format")) {
 258                if (!value)
 259                        return config_error_nonbool(var);
 260                help_format = parse_help_format(value);
 261                return 0;
 262        }
 263        if (!strcmp(var, "help.htmlpath")) {
 264                if (!value)
 265                        return config_error_nonbool(var);
 266                html_path = xstrdup(value);
 267                return 0;
 268        }
 269        if (!strcmp(var, "man.viewer")) {
 270                if (!value)
 271                        return config_error_nonbool(var);
 272                add_man_viewer(value);
 273                return 0;
 274        }
 275        if (starts_with(var, "man."))
 276                return add_man_viewer_info(var, value);
 277
 278        return git_default_config(var, value, cb);
 279}
 280
 281static struct cmdnames main_cmds, other_cmds;
 282
 283static int is_git_command(const char *s)
 284{
 285        if (is_builtin(s))
 286                return 1;
 287
 288        load_command_list("git-", &main_cmds, &other_cmds);
 289        return is_in_cmdlist(&main_cmds, s) ||
 290                is_in_cmdlist(&other_cmds, s);
 291}
 292
 293static const char *cmd_to_page(const char *git_cmd)
 294{
 295        if (!git_cmd)
 296                return "git";
 297        else if (starts_with(git_cmd, "git"))
 298                return git_cmd;
 299        else if (is_git_command(git_cmd))
 300                return xstrfmt("git-%s", git_cmd);
 301        else
 302                return xstrfmt("git%s", git_cmd);
 303}
 304
 305static void setup_man_path(void)
 306{
 307        struct strbuf new_path = STRBUF_INIT;
 308        const char *old_path = getenv("MANPATH");
 309        char *git_man_path = system_path(GIT_MAN_PATH);
 310
 311        /* We should always put ':' after our path. If there is no
 312         * old_path, the ':' at the end will let 'man' to try
 313         * system-wide paths after ours to find the manual page. If
 314         * there is old_path, we need ':' as delimiter. */
 315        strbuf_addstr(&new_path, git_man_path);
 316        strbuf_addch(&new_path, ':');
 317        if (old_path)
 318                strbuf_addstr(&new_path, old_path);
 319
 320        free(git_man_path);
 321        setenv("MANPATH", new_path.buf, 1);
 322
 323        strbuf_release(&new_path);
 324}
 325
 326static void exec_viewer(const char *name, const char *page)
 327{
 328        const char *info = get_man_viewer_info(name);
 329
 330        if (!strcasecmp(name, "man"))
 331                exec_man_man(info, page);
 332        else if (!strcasecmp(name, "woman"))
 333                exec_woman_emacs(info, page);
 334        else if (!strcasecmp(name, "konqueror"))
 335                exec_man_konqueror(info, page);
 336        else if (info)
 337                exec_man_cmd(info, page);
 338        else
 339                warning(_("'%s': unknown man viewer."), name);
 340}
 341
 342static void show_man_page(const char *git_cmd)
 343{
 344        struct man_viewer_list *viewer;
 345        const char *page = cmd_to_page(git_cmd);
 346        const char *fallback = getenv("GIT_MAN_VIEWER");
 347
 348        setup_man_path();
 349        for (viewer = man_viewer_list; viewer; viewer = viewer->next)
 350        {
 351                exec_viewer(viewer->name, page); /* will return when unable */
 352        }
 353        if (fallback)
 354                exec_viewer(fallback, page);
 355        exec_viewer("man", page);
 356        die(_("no man viewer handled the request"));
 357}
 358
 359static void show_info_page(const char *git_cmd)
 360{
 361        const char *page = cmd_to_page(git_cmd);
 362        setenv("INFOPATH", system_path(GIT_INFO_PATH), 1);
 363        execlp("info", "info", "gitman", page, (char *)NULL);
 364        die(_("no info viewer handled the request"));
 365}
 366
 367static void get_html_page_path(struct strbuf *page_path, const char *page)
 368{
 369        struct stat st;
 370        char *to_free = NULL;
 371
 372        if (!html_path)
 373                html_path = to_free = system_path(GIT_HTML_PATH);
 374
 375        /* Check that we have a git documentation directory. */
 376        if (!strstr(html_path, "://")) {
 377                if (stat(mkpath("%s/git.html", html_path), &st)
 378                    || !S_ISREG(st.st_mode))
 379                        die("'%s': not a documentation directory.", html_path);
 380        }
 381
 382        strbuf_init(page_path, 0);
 383        strbuf_addf(page_path, "%s/%s.html", html_path, page);
 384        free(to_free);
 385}
 386
 387static void open_html(const char *path)
 388{
 389        execl_git_cmd("web--browse", "-c", "help.browser", path, (char *)NULL);
 390}
 391
 392static void show_html_page(const char *git_cmd)
 393{
 394        const char *page = cmd_to_page(git_cmd);
 395        struct strbuf page_path; /* it leaks but we exec bellow */
 396
 397        get_html_page_path(&page_path, page);
 398
 399        open_html(page_path.buf);
 400}
 401
 402static struct {
 403        const char *name;
 404        const char *help;
 405} common_guides[] = {
 406        { "attributes", N_("Defining attributes per path") },
 407        { "everyday", N_("Everyday Git With 20 Commands Or So") },
 408        { "glossary", N_("A Git glossary") },
 409        { "ignore", N_("Specifies intentionally untracked files to ignore") },
 410        { "modules", N_("Defining submodule properties") },
 411        { "revisions", N_("Specifying revisions and ranges for Git") },
 412        { "tutorial", N_("A tutorial introduction to Git (for version 1.5.1 or newer)") },
 413        { "workflows", N_("An overview of recommended workflows with Git") },
 414};
 415
 416static void list_common_guides_help(void)
 417{
 418        int i, longest = 0;
 419
 420        for (i = 0; i < ARRAY_SIZE(common_guides); i++) {
 421                if (longest < strlen(common_guides[i].name))
 422                        longest = strlen(common_guides[i].name);
 423        }
 424
 425        puts(_("The common Git guides are:\n"));
 426        for (i = 0; i < ARRAY_SIZE(common_guides); i++) {
 427                printf("   %s   ", common_guides[i].name);
 428                mput_char(' ', longest - strlen(common_guides[i].name));
 429                puts(_(common_guides[i].help));
 430        }
 431        putchar('\n');
 432}
 433
 434static const char *check_git_cmd(const char* cmd)
 435{
 436        char *alias;
 437
 438        if (is_git_command(cmd))
 439                return cmd;
 440
 441        alias = alias_lookup(cmd);
 442        if (alias) {
 443                printf_ln(_("`git %s' is aliased to `%s'"), cmd, alias);
 444                free(alias);
 445                exit(0);
 446        }
 447
 448        if (exclude_guides)
 449                return help_unknown_cmd(cmd);
 450
 451        return cmd;
 452}
 453
 454int cmd_help(int argc, const char **argv, const char *prefix)
 455{
 456        int nongit;
 457        enum help_format parsed_help_format;
 458
 459        argc = parse_options(argc, argv, prefix, builtin_help_options,
 460                        builtin_help_usage, 0);
 461        parsed_help_format = help_format;
 462
 463        if (show_all) {
 464                git_config(git_help_config, NULL);
 465                printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
 466                load_command_list("git-", &main_cmds, &other_cmds);
 467                list_commands(colopts, &main_cmds, &other_cmds);
 468        }
 469
 470        if (show_guides)
 471                list_common_guides_help();
 472
 473        if (show_all || show_guides) {
 474                printf("%s\n", _(git_more_info_string));
 475                /*
 476                * We're done. Ignore any remaining args
 477                */
 478                return 0;
 479        }
 480
 481        if (!argv[0]) {
 482                printf(_("usage: %s%s"), _(git_usage_string), "\n\n");
 483                list_common_cmds_help();
 484                printf("\n%s\n", _(git_more_info_string));
 485                return 0;
 486        }
 487
 488        setup_git_directory_gently(&nongit);
 489        git_config(git_help_config, NULL);
 490
 491        if (parsed_help_format != HELP_FORMAT_NONE)
 492                help_format = parsed_help_format;
 493        if (help_format == HELP_FORMAT_NONE)
 494                help_format = parse_help_format(DEFAULT_HELP_FORMAT);
 495
 496        argv[0] = check_git_cmd(argv[0]);
 497
 498        switch (help_format) {
 499        case HELP_FORMAT_NONE:
 500        case HELP_FORMAT_MAN:
 501                show_man_page(argv[0]);
 502                break;
 503        case HELP_FORMAT_INFO:
 504                show_info_page(argv[0]);
 505                break;
 506        case HELP_FORMAT_WEB:
 507                show_html_page(argv[0]);
 508                break;
 509        }
 510
 511        return 0;
 512}