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-rw-r--r--builtin-help.c241
1 files changed, 241 insertions, 0 deletions
diff --git a/builtin-help.c b/builtin-help.c
new file mode 100644
index 000000000..10a59cc40
--- /dev/null
+++ b/builtin-help.c
@@ -0,0 +1,241 @@
+/*
+ * builtin-help.c
+ *
+ * Builtin help-related commands (help, usage, version)
+ */
+#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;
+}
+
+