1 files changed, 268 insertions, 0 deletions

diff --git a/tools/lib/subcmd/help.c b/tools/lib/subcmd/help.c
new file mode 100644
index 000000000000..e228c3cb3716
--- /dev/null
+++ b/tools/lib/subcmd/help.c
@@ -0,0 +1,268 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <termios.h>
+#include <sys/ioctl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <dirent.h>
+#include "subcmd-util.h"
+#include "help.h"
+#include "exec-cmd.h"
+
+void add_cmdname(struct cmdnames *cmds, const char *name, size_t len)
+{
+        struct cmdname *ent = malloc(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;
+}
+
+void clean_cmdnames(struct cmdnames *cmds)
+{
+        unsigned int i;
+
+        for (i = 0; i < cmds->cnt; ++i)
+                zfree(&cmds->names[i]);
+        zfree(&cmds->names);
+        cmds->cnt = 0;
+        cmds->alloc = 0;
+}
+
+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);
+}
+
+void uniq(struct cmdnames *cmds)
+{
+        unsigned 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)
+{
+        size_t 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 get_term_dimensions(struct winsize *ws)
+{
+        char *s = getenv("LINES");
+
+        if (s != NULL) {
+                ws->ws_row = atoi(s);
+                s = getenv("COLUMNS");
+                if (s != NULL) {
+                        ws->ws_col = atoi(s);
+                        if (ws->ws_row && ws->ws_col)
+                                return;
+                }
+        }
+#ifdef TIOCGWINSZ
+        if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
+            ws->ws_row && ws->ws_col)
+                return;
+#endif
+        ws->ws_row = 25;
+        ws->ws_col = 80;
+}
+
+static void pretty_print_string_list(struct cmdnames *cmds, int longest)
+{
+        int cols = 1, rows;
+        int space = longest + 1; /* min 1 SP between words */
+        struct winsize win;
+        int max_cols;
+        int i, j;
+
+        get_term_dimensions(&win);
+        max_cols = win.ws_col - 1; /* don't print *on* the edge */
+
+        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++) {
+                        unsigned int n = j * rows + i;
+                        unsigned 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;
+
+        return st.st_mode & S_IXUSR;
+}
+
+static int has_extension(const char *filename, const char *ext)
+{
+        size_t len = strlen(filename);
+        size_t extlen = strlen(ext);
+
+        return len > extlen && !memcmp(filename + len - extlen, ext, extlen);
+}
+
+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;
+        char *buf = NULL;
+
+        if (!dir)
+                return;
+        if (!prefix)
+                prefix = "perf-";
+        prefix_len = strlen(prefix);
+
+        astrcatf(&buf, "%s/", path);
+
+        while ((de = readdir(dir)) != NULL) {
+                int entlen;
+
+                if (prefixcmp(de->d_name, prefix))
+                        continue;
+
+                astrcat(&buf, de->d_name);
+                if (!is_executable(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);
+        free(buf);
+}
+
+void load_command_list(const char *prefix,
+                struct cmdnames *main_cmds,
+                struct cmdnames *other_cmds)
+{
+        const char *env_path = getenv("PATH");
+        char *exec_path = get_argv_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 = strdup(env_path);
+                while (1) {
+                        if ((colon = strchr(path, ':')))
+                                *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);
+        }
+        free(exec_path);
+        exclude_cmds(other_cmds, main_cmds);
+}
+
+void list_commands(const char *title, struct cmdnames *main_cmds,
+                   struct cmdnames *other_cmds)
+{
+        unsigned 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) {
+                char *exec_path = get_argv_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');
+                free(exec_path);
+        }
+
+        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)
+{
+        unsigned int i;
+
+        for (i = 0; i < c->cnt; i++)
+                if (!strcmp(s, c->names[i]->name))
+                        return 1;
+        return 0;
+}