diff options
Diffstat (limited to 'help.c')
| -rw-r--r-- | help.c | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/help.c b/help.c new file mode 100644 index 0000000000..37a9c25db7 --- /dev/null +++ b/help.c @@ -0,0 +1,292 @@ +/* + * builtin-help.c + * + * Builtin help-related commands (help, usage, version) + */ +#include "cache.h" +#include "builtin.h" +#include "exec_cmd.h" +#include "common-cmds.h" + +/* most GUI terminals set COLUMNS (although some don't export it) */ +static int term_columns(void) +{ + char *col_string = getenv("COLUMNS"); + int n_cols; + + 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 inline void mput_char(char c, unsigned int num) +{ + while(num--) + putchar(c); +} + +static struct cmdnames { + int alloc; + int cnt; + struct cmdname { + size_t len; + char name[1]; + } **names; +} main_cmds, other_cmds; + +static void add_cmdname(struct cmdnames *cmds, const char *name, int len) +{ + struct cmdname *ent = xmalloc(sizeof(*ent) + len); + + ent->len = len; + memcpy(ent->name, name, len); + ent->name[len] = 0; + + ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc); + cmds->names[cmds->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 uniq(struct cmdnames *cmds) +{ + int i, j; + + if (!cmds->cnt) + return; + + for (i = j = 1; i < cmds->cnt; i++) + if (strcmp(cmds->names[i]->name, cmds->names[i-1]->name)) + cmds->names[j++] = cmds->names[i]; + + cmds->cnt = j; +} + +static void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes) +{ + int ci, cj, ei; + int cmp; + + ci = cj = ei = 0; + while (ci < cmds->cnt && ei < excludes->cnt) { + cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name); + if (cmp < 0) + cmds->names[cj++] = cmds->names[ci++]; + else if (cmp == 0) + ci++, ei++; + else if (cmp > 0) + ei++; + } + + while (ci < cmds->cnt) + cmds->names[cj++] = cmds->names[ci++]; + + cmds->cnt = cj; +} + +static void pretty_print_string_list(struct cmdnames *cmds, 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 = (cmds->cnt + cols - 1) / cols; + + for (i = 0; i < rows; i++) { + printf(" "); + + for (j = 0; j < cols; j++) { + int n = j * rows + i; + int size = space; + if (n >= cmds->cnt) + break; + if (j == cols-1 || n + rows >= cmds->cnt) + size = 1; + printf("%-*s", size, cmds->names[n]->name); + } + putchar('\n'); + } +} + +static unsigned int list_commands_in_dir(struct cmdnames *cmds, + const char *path) +{ + unsigned int longest = 0; + const char *prefix = "git-"; + int prefix_len = strlen(prefix); + DIR *dir = opendir(path); + struct dirent *de; + + if (!dir || chdir(path)) + return 0; + + while ((de = readdir(dir)) != NULL) { + struct stat st; + int entlen; + + if (prefixcmp(de->d_name, prefix)) + continue; + + if (stat(de->d_name, &st) || /* stat, not lstat */ + !S_ISREG(st.st_mode) || + !(st.st_mode & S_IXUSR)) + continue; + + entlen = strlen(de->d_name) - prefix_len; + if (has_extension(de->d_name, ".exe")) + entlen -= 4; + + if (longest < entlen) + longest = entlen; + + add_cmdname(cmds, de->d_name + prefix_len, entlen); + } + closedir(dir); + + return longest; +} + +static void list_commands(void) +{ + unsigned int longest = 0; + unsigned int len; + const char *env_path = getenv("PATH"); + char *paths, *path, *colon; + const char *exec_path = git_exec_path(); + + if (exec_path) + longest = list_commands_in_dir(&main_cmds, exec_path); + + if (!env_path) { + fprintf(stderr, "PATH not set\n"); + exit(1); + } + + path = paths = xstrdup(env_path); + while (1) { + if ((colon = strchr(path, ':'))) + *colon = 0; + + len = list_commands_in_dir(&other_cmds, path); + if (len > longest) + longest = len; + + if (!colon) + break; + path = colon + 1; + } + free(paths); + + qsort(main_cmds.names, main_cmds.cnt, + sizeof(*main_cmds.names), cmdname_compare); + uniq(&main_cmds); + + qsort(other_cmds.names, other_cmds.cnt, + sizeof(*other_cmds.names), cmdname_compare); + uniq(&other_cmds); + exclude_cmds(&other_cmds, &main_cmds); + + if (main_cmds.cnt) { + printf("available git commands in '%s'\n", exec_path); + printf("----------------------------"); + mput_char('-', strlen(exec_path)); + putchar('\n'); + pretty_print_string_list(&main_cmds, longest); + putchar('\n'); + } + + if (other_cmds.cnt) { + printf("git commands available from elsewhere on your $PATH\n"); + printf("---------------------------------------------------\n"); + pretty_print_string_list(&other_cmds, longest); + putchar('\n'); + } +} + +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 void show_man_page(const char *git_cmd) +{ + const char *page; + + if (!prefixcmp(git_cmd, "git")) + page = git_cmd; + else { + int page_len = strlen(git_cmd) + 4; + char *p = xmalloc(page_len + 1); + strcpy(p, "git-"); + strcpy(p + 4, git_cmd); + p[page_len] = 0; + page = p; + } + + execlp("man", "man", page, NULL); +} + +void help_unknown_cmd(const char *cmd) +{ + fprintf(stderr, "git: '%s' is not a git-command. See 'git --help'.\n", cmd); + exit(1); +} + +int cmd_version(int argc, const char **argv, const char *prefix) +{ + printf("git version %s\n", git_version_string); + return 0; +} + +int cmd_help(int argc, const char **argv, const char *prefix) +{ + const char *help_cmd = argc > 1 ? argv[1] : NULL; + + if (!help_cmd) { + printf("usage: %s\n\n", git_usage_string); + list_common_cmds_help(); + exit(0); + } + + else if (!strcmp(help_cmd, "--all") || !strcmp(help_cmd, "-a")) { + printf("usage: %s\n\n", git_usage_string); + list_commands(); + exit(0); + } + + else + show_man_page(help_cmd); + + return 0; +} |