1 files changed, 463 insertions, 0 deletions

diff --git a/Documentation/perf_counter/builtin-help.c b/Documentation/perf_counter/builtin-help.c
new file mode 100644
index 000000000000..125fcc2f4901
--- /dev/null
+++ b/Documentation/perf_counter/builtin-help.c
@@ -0,0 +1,463 @@
+/*
+ * 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_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[] = {
+        "perf 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 = strdup(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 = calloc(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 = calloc(1, sizeof(*new) + len + 1);
+
+        strncpy(new->name, name, len);
+        new->info = strdup(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 perf_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 perf_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 perf 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_perf_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 = malloc(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 *perf_cmd)
+{
+        if (!perf_cmd)
+                return "perf";
+        else if (!prefixcmp(perf_cmd, "perf"))
+                return perf_cmd;
+        else if (is_perf_command(perf_cmd))
+                return prepend("perf-", perf_cmd);
+        else
+                return prepend("perf", perf_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(PERF_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 *perf_cmd)
+{
+        struct man_viewer_list *viewer;
+        const char *page = cmd_to_page(perf_cmd);
+        const char *fallback = getenv("PERF_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 *perf_cmd)
+{
+        const char *page = cmd_to_page(perf_cmd);
+        setenv("INFOPATH", system_path(PERF_INFO_PATH), 1);
+        execlp("info", "info", "perfman", page, NULL);
+}
+
+static void get_html_page_path(struct strbuf *page_path, const char *page)
+{
+        struct stat st;
+        const char *html_path = system_path(PERF_HTML_PATH);
+
+        /* Check that we have a perf documentation directory. */
+        if (stat(mkpath("%s/perf.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
+void open_html(const char *path)
+{
+        execl_perf_cmd("web--browse", "-c", "help.browser", path, NULL);
+}
+#endif
+
+static void show_html_page(const char *perf_cmd)
+{
+        const char *page = cmd_to_page(perf_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 nonperf;
+        const char *alias;
+        load_command_list("perf-", &main_cmds, &other_cmds);
+
+        /* setup_perf_directory_gently(&nonperf); */
+        perf_config(perf_help_config, NULL);
+
+        argc = parse_options(argc, argv, builtin_help_options,
+                        builtin_help_usage, 0);
+
+        if (show_all) {
+                printf("usage: %s\n\n", perf_usage_string);
+                list_commands("perf commands", &main_cmds, &other_cmds);
+                printf("%s\n", perf_more_info_string);
+                return 0;
+        }
+
+        if (!argv[0]) {
+                printf("usage: %s\n\n", perf_usage_string);
+                list_common_cmds_help();
+                printf("\n%s\n", perf_more_info_string);
+                return 0;
+        }
+
+        alias = alias_lookup(argv[0]);
+        if (alias && !is_perf_command(argv[0])) {
+                printf("`perf %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;
+}