*
* Copyright 1999 George Staikos
*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
*
* Changelog:
- * v1.01:
- * - added -p <preload> to preload values from a file
- * v1.01.1
- * - busybox applet aware by <solar@gentoo.org>
- *
+ * v1.01 - added -p <preload> to preload values from a file
+ * v1.01.1 - busybox applet aware by <solar@gentoo.org>
*/
+//config:config BB_SYSCTL
+//config: bool "sysctl (6.9 kb)"
+//config: default y
+//config: help
+//config: Configure kernel parameters at runtime.
-#include "libbb.h"
+//applet:IF_BB_SYSCTL(APPLET_NOEXEC(sysctl, sysctl, BB_DIR_SBIN, BB_SUID_DROP, sysctl))
+
+//kbuild:lib-$(CONFIG_BB_SYSCTL) += sysctl.o
-static int sysctl_act_on_setting(char *setting);
-static int sysctl_display_all(const char *path);
-static int sysctl_handle_preload_file(const char *filename);
-static void sysctl_dots_to_slashes(char *name);
+//usage:#define sysctl_trivial_usage
+//usage: "-p [-enq] [FILE...] / [-enqaw] [KEY[=VALUE]]..."
+//usage:#define sysctl_full_usage "\n\n"
+//usage: "Show/set kernel parameters\n"
+//usage: "\n -p Set values from FILEs (default /etc/sysctl.conf)"
+//usage: "\n -e Don't warn about unknown keys"
+//usage: "\n -n Don't show key names"
+//usage: "\n -q Quiet"
+//usage: "\n -a Show all values"
+/* Same as -a, no need to show it */
+/* //usage: "\n -A Show all values in table form" */
+//usage: "\n -w Set values"
+//usage:
+//usage:#define sysctl_example_usage
+//usage: "sysctl [-n] [-e] variable...\n"
+//usage: "sysctl [-n] [-e] [-q] -w variable=value...\n"
+//usage: "sysctl [-n] [-e] -a\n"
+//usage: "sysctl [-n] [-e] [-q] -p file (default /etc/sysctl.conf)\n"
+//usage: "sysctl [-n] [-e] -A\n"
+
+#include "libbb.h"
enum {
FLAG_SHOW_KEYS = 1 << 0,
FLAG_TABLE_FORMAT = 1 << 2, /* not implemented */
FLAG_SHOW_ALL = 1 << 3,
FLAG_PRELOAD_FILE = 1 << 4,
+ /* NB: procps 3.2.8 does not require -w for KEY=VAL to work, it only rejects non-KEY=VAL form */
FLAG_WRITE = 1 << 5,
+ FLAG_QUIET = 1 << 6,
};
+#define OPTION_STR "neAapwq"
-int sysctl_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int sysctl_main(int argc UNUSED_PARAM, char **argv)
-{
- int retval;
- int opt;
-
- opt = getopt32(argv, "+neAapw"); /* '+' - stop on first non-option */
- argv += optind;
- opt ^= (FLAG_SHOW_KEYS | FLAG_SHOW_KEY_ERRORS);
- option_mask32 = opt;
-
- if (opt & FLAG_PRELOAD_FILE) {
- option_mask32 |= FLAG_WRITE;
- /* xchdir("/proc/sys") is inside */
- return sysctl_handle_preload_file(*argv ? *argv : "/etc/sysctl.conf");
- }
- xchdir("/proc/sys");
- /* xchroot(".") - if you are paranoid */
- if (opt & (FLAG_TABLE_FORMAT | FLAG_SHOW_ALL)) {
- return sysctl_display_all(".");
- }
-
- retval = 0;
- while (*argv) {
- sysctl_dots_to_slashes(*argv);
- retval |= sysctl_display_all(*argv);
- argv++;
- }
-
- return retval;
-}
-
-/* Set sysctl's from a conf file. Format example:
- * # Controls IP packet forwarding
- * net.ipv4.ip_forward = 0
- */
-static int sysctl_handle_preload_file(const char *filename)
+static void sysctl_dots_to_slashes(char *name)
{
- char *token[2];
- parser_t *parser;
+ char *cptr, *last_good, *end;
- parser = config_open(filename);
- /* Must do it _after_ config_open(): */
- xchdir("/proc/sys");
- /* xchroot(".") - if you are paranoid */
+ /* Convert minimum number of '.' to '/' so that
+ * we end up with existing file's name.
+ *
+ * Example from bug 3894:
+ * net.ipv4.conf.eth0.100.mc_forwarding ->
+ * net/ipv4/conf/eth0.100/mc_forwarding
+ * NB: net/ipv4/conf/eth0/mc_forwarding *also exists*,
+ * therefore we must start from the end, and if
+ * we replaced even one . -> /, start over again,
+ * but never replace dots before the position
+ * where last replacement occurred.
+ *
+ * Another bug we later had is that
+ * net.ipv4.conf.eth0.100
+ * (without .mc_forwarding) was mishandled.
+ *
+ * To set up testing: modprobe 8021q; vconfig add eth0 100
+ */
+ end = name + strlen(name);
+ last_good = name - 1;
+ *end = '.'; /* trick the loop into trying full name too */
-//TODO: ';' is comment char too
-//TODO: comment may be only at line start. "var=1 #abc" - "1 #abc" is the value
-// (but _whitespace_ from ends should be trimmed first (and we do it right))
-//TODO: "var==1" is mishandled (must use "=1" as a value, but uses "1")
- while (config_read(parser, token, 2, 2, "# \t=", PARSE_NORMAL)) {
- sysctl_dots_to_slashes(token[0]);
- /* Save ~4 bytes by using parser internals */
- /* parser->line is big enough for sprintf */
- sprintf(parser->line, "%s=%s", token[0], token[1]);
- sysctl_display_all(parser->line);
+ again:
+ cptr = end;
+ while (cptr > last_good) {
+ if (*cptr == '.') {
+ *cptr = '\0';
+ //bb_error_msg("trying:'%s'", name);
+ if (access(name, F_OK) == 0) {
+ *cptr = '/';
+ //bb_error_msg("replaced:'%s'", name);
+ last_good = cptr;
+ goto again;
+ }
+ *cptr = '.';
+ }
+ cptr--;
}
- if (ENABLE_FEATURE_CLEAN_UP)
- config_close(parser);
- return 0;
+ *end = '\0';
}
static int sysctl_act_on_setting(char *setting)
int fd, retval = EXIT_SUCCESS;
char *cptr, *outname;
char *value = value; /* for compiler */
+ bool writing = (option_mask32 & FLAG_WRITE);
outname = xstrdup(setting);
cptr++;
}
- if (option_mask32 & FLAG_WRITE) {
- cptr = strchr(setting, '=');
+ cptr = strchr(setting, '=');
+ if (cptr)
+ writing = 1;
+ if (writing) {
if (cptr == NULL) {
bb_error_msg("error: '%s' must be of the form name=value",
outname);
retval = EXIT_FAILURE;
goto end;
}
- value = cptr + 1; /* point to the value in name=value */
+ value = cptr + 1; /* point to the value in name=value */
if (setting == cptr || !*value) {
bb_error_msg("error: malformed setting '%s'", outname);
retval = EXIT_FAILURE;
if (fd < 0) {
switch (errno) {
+ case EACCES:
+ /* Happens for write-only settings, e.g. net.ipv6.route.flush */
+ goto end;
case ENOENT:
if (option_mask32 & FLAG_SHOW_KEY_ERRORS)
bb_error_msg("error: '%s' is an unknown key", outname);
break;
default:
bb_perror_msg("error %sing key '%s'",
- option_mask32 & FLAG_WRITE ?
+ writing ?
"sett" : "read",
outname);
break;
goto end;
}
- if (option_mask32 & FLAG_WRITE) {
+ if (writing) {
//TODO: procps 3.2.7 writes "value\n", note trailing "\n"
xwrite_str(fd, value);
close(fd);
- if (option_mask32 & FLAG_SHOW_KEYS)
- printf("%s = ", outname);
- puts(value);
+ if (!(option_mask32 & FLAG_QUIET)) {
+ if (option_mask32 & FLAG_SHOW_KEYS)
+ printf("%s = ", outname);
+ puts(value);
+ }
} else {
char c;
return retval;
}
-static int sysctl_display_all(const char *path)
+static int sysctl_act_recursive(const char *path)
{
DIR *dirp;
struct stat buf;
if (next == NULL)
continue; /* d_name is "." or ".." */
/* if path was ".", drop "./" prefix: */
- retval |= sysctl_display_all((next[0] == '.' && next[1] == '/') ?
- next + 2 : next);
+ retval |= sysctl_act_recursive((next[0] == '.' && next[1] == '/') ?
+ next + 2 : next);
free(next);
}
closedir(dirp);
return retval;
}
-static void sysctl_dots_to_slashes(char *name)
+/* Set sysctl's from a conf file. Format example:
+ * # Controls IP packet forwarding
+ * net.ipv4.ip_forward = 0
+ */
+static int sysctl_handle_preload_file(const char *filename)
{
- char *cptr, *last_good, *end;
+ char *token[2];
+ parser_t *parser;
+ int parse_flags;
- /* Convert minimum number of '.' to '/' so that
- * we end up with existing file's name.
- *
- * Example from bug 3894:
- * net.ipv4.conf.eth0.100.mc_forwarding ->
- * net/ipv4/conf/eth0.100/mc_forwarding
- * NB: net/ipv4/conf/eth0/mc_forwarding *also exists*,
- * therefore we must start from the end, and if
- * we replaced even one . -> /, start over again,
- * but never replace dots before the position
- * where last replacement occurred.
- *
- * Another bug we later had is that
- * net.ipv4.conf.eth0.100
- * (without .mc_forwarding) was mishandled.
- *
- * To set up testing: modprobe 8021q; vconfig add eth0 100
- */
- end = name + strlen(name);
- last_good = name - 1;
- *end = '.'; /* trick the loop into trying full name too */
+ parser = config_open(filename);
+ /* Must do it _after_ config_open(): */
+ xchdir("/proc/sys");
- again:
- cptr = end;
- while (cptr > last_good) {
- if (*cptr == '.') {
- *cptr = '\0';
- //bb_error_msg("trying:'%s'", name);
- if (access(name, F_OK) == 0) {
- if (cptr != end) /* prevent trailing '/' */
- *cptr = '/';
- //bb_error_msg("replaced:'%s'", name);
- last_good = cptr;
- goto again;
- }
- *cptr = '.';
- }
- cptr--;
+ parse_flags = 0;
+ parse_flags &= ~PARSE_COLLAPSE; // NO (var==val is not var=val) - treat consecutive delimiters as one
+ parse_flags &= ~PARSE_TRIM; // NO - trim leading and trailing delimiters
+ parse_flags |= PARSE_GREEDY; // YES - last token takes entire remainder of the line
+ parse_flags &= ~PARSE_MIN_DIE; // NO - die if < min tokens found
+ parse_flags &= ~PARSE_EOL_COMMENTS; // NO (only first char) - comments are recognized even if not first char
+ parse_flags |= PARSE_ALT_COMMENTS;// YES - two comment chars: ';' and '#'
+ /* <space><tab><space>#comment is also comment, not strictly 1st char only */
+ parse_flags |= PARSE_WS_COMMENTS; // YES - comments are recognized even if there is whitespace before
+ while (config_read(parser, token, 2, 2, ";#=", parse_flags)) {
+ char *tp;
+
+ trim(token[1]);
+ tp = trim(token[0]);
+ sysctl_dots_to_slashes(token[0]);
+ /* ^^^converted in-place. tp still points to NUL */
+ /* now, add "=TOKEN1" */
+ *tp++ = '=';
+ overlapping_strcpy(tp, token[1]);
+
+ sysctl_act_on_setting(token[0]);
}
- *end = '\0';
+ if (ENABLE_FEATURE_CLEAN_UP)
+ config_close(parser);
+ return 0;
+}
+
+int sysctl_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int sysctl_main(int argc UNUSED_PARAM, char **argv)
+{
+ int retval;
+ int opt;
+
+ opt = getopt32(argv, "+" OPTION_STR); /* '+' - stop on first non-option */
+ argv += optind;
+ opt ^= (FLAG_SHOW_KEYS | FLAG_SHOW_KEY_ERRORS);
+ option_mask32 = opt;
+
+ if (opt & FLAG_PRELOAD_FILE) {
+ int cur_dir_fd;
+ option_mask32 |= FLAG_WRITE;
+ if (!*argv)
+ *--argv = (char*)"/etc/sysctl.conf";
+ cur_dir_fd = xopen(".", O_RDONLY | O_DIRECTORY);
+ do {
+ /* xchdir("/proc/sys") is inside */
+ sysctl_handle_preload_file(*argv);
+ xfchdir(cur_dir_fd); /* files can be relative, must restore cwd */
+ } while (*++argv);
+ return 0; /* procps-ng 3.3.10 does not flag parse errors */
+ }
+ xchdir("/proc/sys");
+ if (opt & (FLAG_TABLE_FORMAT | FLAG_SHOW_ALL)) {
+ return sysctl_act_recursive(".");
+ }
+
+ retval = 0;
+ while (*argv) {
+ sysctl_dots_to_slashes(*argv);
+ retval |= sysctl_act_recursive(*argv);
+ argv++;
+ }
+
+ return retval;
}
projects / oweals / busybox.git / blobdiff