* 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.
+
+//applet:IF_BB_SYSCTL(APPLET_NOEXEC(sysctl, sysctl, BB_DIR_SBIN, BB_SUID_DROP, sysctl))
+
+//kbuild:lib-$(CONFIG_BB_SYSCTL) += sysctl.o
//usage:#define sysctl_trivial_usage
-//usage: "[OPTIONS] [KEY[=VALUE]]..."
+//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: "\n -p FILE Set values from FILE (default /etc/sysctl.conf)"
-//usage: "\n -q Set values silently"
//usage:
//usage:#define sysctl_example_usage
//usage: "sysctl [-n] [-e] variable...\n"
FLAG_TABLE_FORMAT = 1 << 2, /* not implemented */
FLAG_SHOW_ALL = 1 << 3,
FLAG_PRELOAD_FILE = 1 << 4,
-/* TODO: procps 3.2.8 seems to not require -w for KEY=VAL to work: */
+ /* 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,
};
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);
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);
{
char *token[2];
parser_t *parser;
+ int parse_flags;
parser = config_open(filename);
/* Must do it _after_ config_open(): */
xchdir("/proc/sys");
- /* xchroot("/proc/sys") - if you are paranoid */
-//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")
-// can it be fixed by removing PARSE_COLLAPSE bit?
- while (config_read(parser, token, 2, 2, "# \t=", PARSE_NORMAL)) {
+ 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]);
- tp = xasprintf("%s=%s", token[0], token[1]);
- sysctl_act_recursive(tp);
- free(tp);
+ /* ^^^converted in-place. tp still points to NUL */
+ /* now, add "=TOKEN1" */
+ *tp++ = '=';
+ overlapping_strcpy(tp, token[1]);
+
+ sysctl_act_on_setting(token[0]);
}
if (ENABLE_FEATURE_CLEAN_UP)
config_close(parser);
option_mask32 = opt;
if (opt & FLAG_PRELOAD_FILE) {
+ int cur_dir_fd;
option_mask32 |= FLAG_WRITE;
- /* xchdir("/proc/sys") is inside */
- return sysctl_handle_preload_file(*argv ? *argv : "/etc/sysctl.conf");
+ 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");
- /* xchroot("/proc/sys") - if you are paranoid */
if (opt & (FLAG_TABLE_FORMAT | FLAG_SHOW_ALL)) {
return sysctl_act_recursive(".");
}