cpupower: use man(1) when calling "cpupower help subcommand"
Instead of printing something non-formatted to stdout, call
man(1) to show the man page for the proper subcommand.
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
diff --git a/tools/power/cpupower/utils/cpupower.c b/tools/power/cpupower/utils/cpupower.c
index 5844ae0..52bee59 100644
--- a/tools/power/cpupower/utils/cpupower.c
+++ b/tools/power/cpupower/utils/cpupower.c
@@ -11,6 +11,7 @@
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
+#include <errno.h>
#include "builtin.h"
#include "helpers/helpers.h"
@@ -19,13 +20,12 @@
struct cmd_struct {
const char *cmd;
int (*main)(int, const char **);
- void (*usage)(void);
int needs_root;
};
#define ARRAY_SIZE(x) (sizeof(x)/sizeof(x[0]))
-int cmd_help(int argc, const char **argv);
+static int cmd_help(int argc, const char **argv);
/* Global cpu_info object available for all binaries
* Info only retrieved from CPU 0
@@ -44,55 +44,66 @@
static void print_help(void);
static struct cmd_struct commands[] = {
- { "frequency-info", cmd_freq_info, freq_info_help, 0 },
- { "frequency-set", cmd_freq_set, freq_set_help, 1 },
- { "idle-info", cmd_idle_info, idle_info_help, 0 },
- { "set", cmd_set, set_help, 1 },
- { "info", cmd_info, info_help, 0 },
- { "monitor", cmd_monitor, monitor_help, 0 },
- { "help", cmd_help, print_help, 0 },
- /* { "bench", cmd_bench, NULL, 1 }, */
+ { "frequency-info", cmd_freq_info, 0 },
+ { "frequency-set", cmd_freq_set, 1 },
+ { "idle-info", cmd_idle_info, 0 },
+ { "set", cmd_set, 1 },
+ { "info", cmd_info, 0 },
+ { "monitor", cmd_monitor, 0 },
+ { "help", cmd_help, 0 },
+ /* { "bench", cmd_bench, 1 }, */
};
-int cmd_help(int argc, const char **argv)
-{
- unsigned int i;
-
- if (argc > 1) {
- for (i = 0; i < ARRAY_SIZE(commands); i++) {
- struct cmd_struct *p = commands + i;
- if (strcmp(p->cmd, argv[1]))
- continue;
- if (p->usage) {
- p->usage();
- return EXIT_SUCCESS;
- }
- }
- }
- print_help();
- if (argc == 1)
- return EXIT_SUCCESS; /* cpupower help */
- return EXIT_FAILURE;
-}
-
static void print_help(void)
{
unsigned int i;
#ifdef DEBUG
- printf(_("cpupower [ -d ][ -c cpulist ] subcommand [ARGS]\n"));
- printf(_(" -d, --debug May increase output (stderr) on some subcommands\n"));
+ printf(_("Usage:\tcpupower [-d|--debug] [-c|--cpu cpulist ] <command> [<args>]\n"));
#else
- printf(_("cpupower [ -c cpulist ] subcommand [ARGS]\n"));
+ printf(_("Usage:\tcpupower [-c|--cpu cpulist ] <command> [<args>]\n"));
#endif
- printf(_("cpupower --version\n"));
- printf(_("Supported subcommands are:\n"));
+ printf(_("Supported commands are:\n"));
for (i = 0; i < ARRAY_SIZE(commands); i++)
printf("\t%s\n", commands[i].cmd);
- printf(_("\nSome subcommands can make use of the -c cpulist option.\n"));
- printf(_("Look at the general cpupower manpage how to use it\n"));
- printf(_("and read up the subcommand's manpage whether it is supported.\n"));
- printf(_("\nUse cpupower help subcommand for getting help for above subcommands.\n"));
+ printf(_("\nNot all commands can make use of the -c cpulist option.\n"));
+ printf(_("\nUse 'cpupower help <command>' for getting help for above commands.\n"));
+}
+
+static int print_man_page(const char *subpage)
+{
+ int len;
+ char *page;
+
+ len = 10; /* enough for "cpupower-" */
+ if (subpage != NULL)
+ len += strlen(subpage);
+
+ page = malloc(len);
+ if (!page)
+ return -ENOMEM;
+
+ sprintf(page, "cpupower");
+ if ((subpage != NULL) && strcmp(subpage, "help")) {
+ strcat(page, "-");
+ strcat(page, subpage);
+ }
+
+ execlp("man", "man", page, NULL);
+
+ /* should not be reached */
+ return -EINVAL;
+}
+
+static int cmd_help(int argc, const char **argv)
+{
+ if (argc > 1) {
+ print_man_page(argv[1]); /* exits within execlp() */
+ return EXIT_FAILURE;
+ }
+
+ print_help();
+ return EXIT_SUCCESS;
}
static void print_version(void)
