diff options
Diffstat (limited to 'builtin-help.c')
| -rw-r--r-- | builtin-help.c | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/builtin-help.c b/builtin-help.c new file mode 100644 index 0000000000..7470faa566 --- /dev/null +++ b/builtin-help.c @@ -0,0 +1,242 @@ +/* + * builtin-help.c + * + * Builtin help-related commands (help, usage, version) + */ +#include <sys/ioctl.h> +#include "cache.h" +#include "builtin.h" +#include "exec_cmd.h" +#include "common-cmds.h" + +static const char git_usage[] = + "Usage: git [--version] [--exec-path[=GIT_EXEC_PATH]] [--help] COMMAND [ ARGS ]"; + +/* most gui terms set COLUMNS (although some don't export it) */ +static int term_columns(void) +{ + char *col_string = getenv("COLUMNS"); + int n_cols = 0; + + 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 void oom(void) +{ + fprintf(stderr, "git: out of memory\n"); + exit(1); +} + +static inline void mput_char(char c, unsigned int num) +{ + while(num--) + putchar(c); +} + +static struct cmdname { + size_t len; + char name[1]; +} **cmdname; +static int cmdname_alloc, cmdname_cnt; + +static void add_cmdname(const char *name, int len) +{ + struct cmdname *ent; + if (cmdname_alloc <= cmdname_cnt) { + cmdname_alloc = cmdname_alloc + 200; + cmdname = realloc(cmdname, cmdname_alloc * sizeof(*cmdname)); + if (!cmdname) + oom(); + } + ent = malloc(sizeof(*ent) + len); + if (!ent) + oom(); + ent->len = len; + memcpy(ent->name, name, len); + ent->name[len] = 0; + cmdname[cmdname_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 pretty_print_string_list(struct cmdname **cmdname, 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 = (cmdname_cnt + cols - 1) / cols; + + qsort(cmdname, cmdname_cnt, sizeof(*cmdname), cmdname_compare); + + for (i = 0; i < rows; i++) { + printf(" "); + + for (j = 0; j < cols; j++) { + int n = j * rows + i; + int size = space; + if (n >= cmdname_cnt) + break; + if (j == cols-1 || n + rows >= cmdname_cnt) + size = 1; + printf("%-*s", size, cmdname[n]->name); + } + putchar('\n'); + } +} + +static void list_commands(const char *exec_path, const char *pattern) +{ + unsigned int longest = 0; + char path[PATH_MAX]; + int dirlen; + DIR *dir = opendir(exec_path); + struct dirent *de; + + if (!dir) { + fprintf(stderr, "git: '%s': %s\n", exec_path, strerror(errno)); + exit(1); + } + + dirlen = strlen(exec_path); + if (PATH_MAX - 20 < dirlen) { + fprintf(stderr, "git: insanely long exec-path '%s'\n", + exec_path); + exit(1); + } + + memcpy(path, exec_path, dirlen); + path[dirlen++] = '/'; + + while ((de = readdir(dir)) != NULL) { + struct stat st; + int entlen; + + if (strncmp(de->d_name, "git-", 4)) + continue; + strcpy(path+dirlen, de->d_name); + if (stat(path, &st) || /* stat, not lstat */ + !S_ISREG(st.st_mode) || + !(st.st_mode & S_IXUSR)) + continue; + + entlen = strlen(de->d_name); + if (4 < entlen && !strcmp(de->d_name + entlen - 4, ".exe")) + entlen -= 4; + + if (longest < entlen) + longest = entlen; + + add_cmdname(de->d_name + 4, entlen-4); + } + closedir(dir); + + printf("git commands available in '%s'\n", exec_path); + printf("----------------------------"); + mput_char('-', strlen(exec_path)); + putchar('\n'); + pretty_print_string_list(cmdname, longest - 4); + putchar('\n'); +} + +static 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) + 4); + puts(common_cmds[i].help); + } + puts("(use 'git help -a' to get a list of all installed git commands)"); +} + +void cmd_usage(int show_all, const char *exec_path, const char *fmt, ...) +{ + if (fmt) { + va_list ap; + + va_start(ap, fmt); + printf("git: "); + vprintf(fmt, ap); + va_end(ap); + putchar('\n'); + } + else + puts(git_usage); + + if (exec_path) { + putchar('\n'); + if (show_all) + list_commands(exec_path, "git-*"); + else + list_common_cmds_help(); + } + + exit(1); +} + +static void show_man_page(const char *git_cmd) +{ + const char *page; + + if (!strncmp(git_cmd, "git", 3)) + page = git_cmd; + else { + int page_len = strlen(git_cmd) + 4; + char *p = malloc(page_len + 1); + strcpy(p, "git-"); + strcpy(p + 4, git_cmd); + p[page_len] = 0; + page = p; + } + + execlp("man", "man", page, NULL); +} + +int cmd_version(int argc, const char **argv, char **envp) +{ + printf("git version %s\n", git_version_string); + return 0; +} + +int cmd_help(int argc, const char **argv, char **envp) +{ + const char *help_cmd = argv[1]; + if (!help_cmd) + cmd_usage(0, git_exec_path(), NULL); + else if (!strcmp(help_cmd, "--all") || !strcmp(help_cmd, "-a")) + cmd_usage(1, git_exec_path(), NULL); + else + show_man_page(help_cmd); + return 0; +} + + |