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-rw-r--r--help.c370
1 files changed, 370 insertions, 0 deletions
diff --git a/help.c b/help.c
new file mode 100644
index 0000000..7f4928e
--- /dev/null
+++ b/help.c
@@ -0,0 +1,370 @@
+#include "cache.h"
+#include "builtin.h"
+#include "exec_cmd.h"
+#include "levenshtein.h"
+#include "help.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;
+}
+
+void add_cmdname(struct cmdnames *cmds, const char *name, int len)
+{
+ struct cmdname *ent = xmalloc(sizeof(*ent) + len + 1);
+
+ 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 void clean_cmdnames(struct cmdnames *cmds)
+{
+ int i;
+ for (i = 0; i < cmds->cnt; ++i)
+ free(cmds->names[i]);
+ free(cmds->names);
+ cmds->cnt = 0;
+ cmds->alloc = 0;
+}
+
+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;
+}
+
+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 = DIV_ROUND_UP(cmds->cnt, 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 int is_executable(const char *name)
+{
+ struct stat st;
+
+ if (stat(name, &st) || /* stat, not lstat */
+ !S_ISREG(st.st_mode))
+ return 0;
+
+#ifdef WIN32
+{ /* cannot trust the executable bit, peek into the file instead */
+ char buf[3] = { 0 };
+ int n;
+ int fd = open(name, O_RDONLY);
+ st.st_mode &= ~S_IXUSR;
+ if (fd >= 0) {
+ n = read(fd, buf, 2);
+ if (n == 2)
+ /* DOS executables start with "MZ" */
+ if (!strcmp(buf, "#!") || !strcmp(buf, "MZ"))
+ st.st_mode |= S_IXUSR;
+ close(fd);
+ }
+}
+#endif
+ return st.st_mode & S_IXUSR;
+}
+
+static void list_commands_in_dir(struct cmdnames *cmds,
+ const char *path,
+ const char *prefix)
+{
+ int prefix_len;
+ DIR *dir = opendir(path);
+ struct dirent *de;
+ struct strbuf buf = STRBUF_INIT;
+ int len;
+
+ if (!dir)
+ return;
+ if (!prefix)
+ prefix = "git-";
+ prefix_len = strlen(prefix);
+
+ strbuf_addf(&buf, "%s/", path);
+ len = buf.len;
+
+ while ((de = readdir(dir)) != NULL) {
+ int entlen;
+
+ if (prefixcmp(de->d_name, prefix))
+ continue;
+
+ strbuf_setlen(&buf, len);
+ strbuf_addstr(&buf, de->d_name);
+ if (!is_executable(buf.buf))
+ continue;
+
+ entlen = strlen(de->d_name) - prefix_len;
+ if (has_extension(de->d_name, ".exe"))
+ entlen -= 4;
+
+ add_cmdname(cmds, de->d_name + prefix_len, entlen);
+ }
+ closedir(dir);
+ strbuf_release(&buf);
+}
+
+void load_command_list(const char *prefix,
+ struct cmdnames *main_cmds,
+ struct cmdnames *other_cmds)
+{
+ const char *env_path = getenv("PATH");
+ const char *exec_path = git_exec_path();
+
+ if (exec_path) {
+ list_commands_in_dir(main_cmds, exec_path, prefix);
+ qsort(main_cmds->names, main_cmds->cnt,
+ sizeof(*main_cmds->names), cmdname_compare);
+ uniq(main_cmds);
+ }
+
+ if (env_path) {
+ char *paths, *path, *colon;
+ path = paths = xstrdup(env_path);
+ while (1) {
+ if ((colon = strchr(path, PATH_SEP)))
+ *colon = 0;
+ if (!exec_path || strcmp(path, exec_path))
+ list_commands_in_dir(other_cmds, path, prefix);
+
+ if (!colon)
+ break;
+ path = colon + 1;
+ }
+ free(paths);
+
+ qsort(other_cmds->names, other_cmds->cnt,
+ sizeof(*other_cmds->names), cmdname_compare);
+ uniq(other_cmds);
+ }
+ exclude_cmds(other_cmds, main_cmds);
+}
+
+void list_commands(const char *title, struct cmdnames *main_cmds,
+ struct cmdnames *other_cmds)
+{
+ int i, longest = 0;
+
+ for (i = 0; i < main_cmds->cnt; i++)
+ if (longest < main_cmds->names[i]->len)
+ longest = main_cmds->names[i]->len;
+ for (i = 0; i < other_cmds->cnt; i++)
+ if (longest < other_cmds->names[i]->len)
+ longest = other_cmds->names[i]->len;
+
+ if (main_cmds->cnt) {
+ const char *exec_path = git_exec_path();
+ printf("available %s in '%s'\n", title, exec_path);
+ printf("----------------");
+ mput_char('-', strlen(title) + strlen(exec_path));
+ putchar('\n');
+ pretty_print_string_list(main_cmds, longest);
+ putchar('\n');
+ }
+
+ if (other_cmds->cnt) {
+ printf("%s available from elsewhere on your $PATH\n", title);
+ printf("---------------------------------------");
+ mput_char('-', strlen(title));
+ putchar('\n');
+ pretty_print_string_list(other_cmds, longest);
+ putchar('\n');
+ }
+}
+
+int is_in_cmdlist(struct cmdnames *c, const char *s)
+{
+ int i;
+ for (i = 0; i < c->cnt; i++)
+ if (!strcmp(s, c->names[i]->name))
+ return 1;
+ return 0;
+}
+
+static int autocorrect;
+static struct cmdnames aliases;
+
+static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
+{
+ if (!strcmp(var, "help.autocorrect"))
+ autocorrect = git_config_int(var,value);
+ /* Also use aliases for command lookup */
+ if (!prefixcmp(var, "alias."))
+ add_cmdname(&aliases, var + 6, strlen(var + 6));
+
+ return git_default_config(var, value, cb);
+}
+
+static int levenshtein_compare(const void *p1, const void *p2)
+{
+ const struct cmdname *const *c1 = p1, *const *c2 = p2;
+ const char *s1 = (*c1)->name, *s2 = (*c2)->name;
+ int l1 = (*c1)->len;
+ int l2 = (*c2)->len;
+ return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
+}
+
+static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
+{
+ int i;
+ ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
+
+ for (i = 0; i < old->cnt; i++)
+ cmds->names[cmds->cnt++] = old->names[i];
+ free(old->names);
+ old->cnt = 0;
+ old->names = NULL;
+}
+
+/* An empirically derived magic number */
+#define SIMILAR_ENOUGH(x) ((x) < 6)
+
+const char *help_unknown_cmd(const char *cmd)
+{
+ int i, n, best_similarity = 0;
+ struct cmdnames main_cmds, other_cmds;
+
+ memset(&main_cmds, 0, sizeof(main_cmds));
+ memset(&other_cmds, 0, sizeof(other_cmds));
+ memset(&aliases, 0, sizeof(aliases));
+
+ git_config(git_unknown_cmd_config, NULL);
+
+ load_command_list("git-", &main_cmds, &other_cmds);
+
+ add_cmd_list(&main_cmds, &aliases);
+ add_cmd_list(&main_cmds, &other_cmds);
+ qsort(main_cmds.names, main_cmds.cnt,
+ sizeof(main_cmds.names), cmdname_compare);
+ uniq(&main_cmds);
+
+ /* This reuses cmdname->len for similarity index */
+ for (i = 0; i < main_cmds.cnt; ++i)
+ main_cmds.names[i]->len =
+ levenshtein(cmd, main_cmds.names[i]->name, 0, 2, 1, 4);
+
+ qsort(main_cmds.names, main_cmds.cnt,
+ sizeof(*main_cmds.names), levenshtein_compare);
+
+ if (!main_cmds.cnt)
+ die ("Uh oh. Your system reports no Git commands at all.");
+
+ best_similarity = main_cmds.names[0]->len;
+ n = 1;
+ while (n < main_cmds.cnt && best_similarity == main_cmds.names[n]->len)
+ ++n;
+ if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
+ const char *assumed = main_cmds.names[0]->name;
+ main_cmds.names[0] = NULL;
+ clean_cmdnames(&main_cmds);
+ fprintf(stderr, "WARNING: You called a Git command named '%s', "
+ "which does not exist.\n"
+ "Continuing under the assumption that you meant '%s'\n",
+ cmd, assumed);
+ if (autocorrect > 0) {
+ fprintf(stderr, "in %0.1f seconds automatically...\n",
+ (float)autocorrect/10.0);
+ poll(NULL, 0, autocorrect * 100);
+ }
+ return assumed;
+ }
+
+ fprintf(stderr, "git: '%s' is not a git command. See 'git --help'.\n", cmd);
+
+ if (SIMILAR_ENOUGH(best_similarity)) {
+ fprintf(stderr, "\nDid you mean %s?\n",
+ n < 2 ? "this": "one of these");
+
+ for (i = 0; i < n; i++)
+ fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
+ }
+
+ exit(1);
+}
+
+int cmd_version(int argc, const char **argv, const char *prefix)
+{
+ printf("git version %s\n", git_version_string);
+ return 0;
+}