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Diffstat (limited to 'toys')
-rw-r--r--toys/pending/sysctl.c249
1 files changed, 94 insertions, 155 deletions
diff --git a/toys/pending/sysctl.c b/toys/pending/sysctl.c
index 7e8736d7..741b8aef 100644
--- a/toys/pending/sysctl.c
+++ b/toys/pending/sysctl.c
@@ -11,38 +11,29 @@ config SYSCTL
bool "sysctl"
default n
help
- usage: sysctl [OPTIONS] [KEY[=VALUE]]...
+ usage: sysctl [-aAeNnqw] [-p [FILE] | KEY[=VALUE]...]
- Configure kernel parameters at runtime.
+ Read/write system control data (under /proc/sys).
- -a, A Show all values
- -e Don't warn about unknown keys
- -N Show only key names
- -n Show only key values
- -p FILE Set values from FILE (default /etc/sysctl.conf)
- -q Set values silently
- -w Set values
+ -a,A Show all values
+ -e Don't warn about unknown keys
+ -N Don't print key values
+ -n Don't print key names
+ -p [FILE] Read values from FILE (default /etc/sysctl.conf)
+ -q Don't show value after write
+ -w Only write values (object to reading)
*/
#define FOR_sysctl
#include "toys.h"
-#define PROC_SYS_DIR "/proc/sys"
-#define MAX_BYTES_LINE 1024
-
-static void parse_key_name_value(char *param, char **key_name, char **key_value)
+// Null terminate at =, return value
+static char *split_key(char *key)
{
- char *name, *value;
-
- if (!(name = strchr(param, '='))) goto show_error_msg;
- value = name;
- value++;
- if (!(*value)) goto show_error_msg;
- *name = '\0';
- *key_name = param;
- *key_value = value;
- return;
-show_error_msg:
- error_msg("error: '%s' must be of the form name=value", param);
+ char *value = strchr(key, '=');
+
+ if (value) *(value++)=0;
+
+ return value;
}
static void replace_char(char *str, char old, char new)
@@ -50,159 +41,107 @@ static void replace_char(char *str, char old, char new)
for (; *str; str++) if (*str == old) *str = new;
}
-static void handle_file_error(char *key_name)
+static void key_error(char *key)
{
- replace_char(key_name, '/', '.');
- if (errno == ENOENT) {
- if (!(toys.optflags & FLAG_e))
- error_msg("error: '%s' is an unknown key", key_name);
- else toys.exitval = 1;
- } else perror_msg("error: %s key '%s'", (toys.optflags & FLAG_w) ?
- "setting" : "reading", key_name);
+ if (!(errno == ENOENT && (toys.optflags & FLAG_e)))
+ perror_msg("key '%s'", key);
}
-static void write_to_file(char *fpath, char *key_name, char *key_value)
+static int write_key(char *path, char *key, char *value)
{
- int fd;
+ int fd = open(path, O_WRONLY);;
- replace_char(key_name, '.', '/');
- sprintf(toybuf, "%s/%s", fpath, key_name);
- if ((fd = open(toybuf, O_WRONLY)) < 0) {
- handle_file_error(key_name);
- return;
+ if (fd < 0) {
+ key_error(key);
+
+ return 0;
}
- xwrite(fd, key_value, strlen(key_value));
+ xwrite(fd, value, strlen(value));
xclose(fd);
- if (!(toys.optflags & FLAG_q)) {
- replace_char(key_name, '/', '.');
- if (toys.optflags & FLAG_N) xprintf("%s\n", key_name);
- else if (toys.optflags & FLAG_n) xprintf("%s\n", key_value);
- else xprintf("%s = %s\n", key_name, key_value);
- }
-}
-static char *get_key_value(char *buff, int *offset)
-{
- char *line, *tmp = buff + *offset;
- int index = 0, multiplier = 1;
-
- if (!*tmp) return 0;
- line = xmalloc(MAX_BYTES_LINE);
- for (; *tmp != '\n'; tmp++) {
- line[index++] = *tmp;
- if (MAX_BYTES_LINE == index) { // buffer overflow
- multiplier++;
- line = (char *) xrealloc(line, multiplier * MAX_BYTES_LINE);
- }
- }
- line[index++] = '\0';
- *offset += index;
- return line;
+ return 1;
}
-static void trim_spaces(char **param)
+// Display all keys under a path
+static int do_show_keys(struct dirtree *dt)
{
- int len = 0;
- char *str = *param, *p_start = str, *p_end;
-
- if (p_start) { // start pointer to string
- p_end = str + strlen(str) - 1; // end pointer to string
- while (*p_start == ' ') p_start++;
- str = p_start;
- while (*p_end == ' ') p_end--;
- p_end++;
- *p_end = '\0';
- len = (int) (p_end - str) + 1;
- memmove(*param, str, len);
- }
-}
+ char *path, *data, *key;
-// Read config file and write values to corresponding key name files
-static void read_config_file(char *fname)
-{
- char *line, *name = NULL, *value = NULL;
- int fd = xopen(fname, O_RDONLY);
-
- for (; (line = get_line(fd)); free(line), name = NULL, value = NULL) {
- char *ptr = line;
-
- while (*ptr == ' ' || *ptr == '\t') ptr++;
- if (*ptr != '#' && *ptr != ';' && *ptr !='\n' && *ptr) {
- parse_key_name_value(ptr, &name, &value);
- trim_spaces(&name);
- trim_spaces(&value);
- if (name && value) write_to_file(PROC_SYS_DIR, name, value);
- }
+ if (!dirtree_notdotdot(dt)) return 0; // Skip . and ..
+ if (S_ISDIR(dt->st.st_mode)) return DIRTREE_RECURSE;
+
+ path = dirtree_path(dt, 0);
+ data = readfile(path, 0, 0);
+ replace_char(key = path + 10, '/', '.'); // skip "/proc/sys/"
+ if (!data) key_error(key);
+ else {
+ // Print the parts that aren't switched off by flags.
+ if (!(toys.optflags & FLAG_n)) xprintf("%s", key);
+ if (!(toys.optflags & (FLAG_N|FLAG_n))) xprintf(" = ");
+ for (key = data+strlen(data); key > data && isspace(*--key); *key = 0);
+ if (!(toys.optflags & FLAG_N)) xprintf("%s", data);
+ if ((toys.optflags & (FLAG_N|FLAG_n)) != (FLAG_N|FLAG_n)) xputc('\n');
}
- xclose(fd);
-}
-// Open file for each and every key name and read file contents
-void read_key_values(char *fpath)
-{
- char *key_value, *fdata, *key_name, *tmp = xstrdup(fpath);
- int offset = 0;
-
- key_name = (tmp + strlen(PROC_SYS_DIR) + 1);
- replace_char(key_name, '/', '.');
- if (!(fdata = readfile(fpath, NULL, 0))) {
- handle_file_error(key_name);
- free(tmp);
- return;
- }
- if (toys.optflags & FLAG_N) {
- xprintf("%s\n", key_name);
- free(tmp);
- free(fdata);
- return;
- }
- for (; (key_value = get_key_value(fdata, &offset)); free(key_value)) {
- if (!(toys.optflags & FLAG_q)) {
- if (!(toys.optflags & FLAG_n)) xprintf("%s = ", key_name);
- xprintf("%s\n", key_value);
- }
- }
- free(tmp);
- free(fdata);
+ free(data);
+ free(path);
+
+ return 0;
}
-static int do_flag_a(struct dirtree *dt)
+// Read/write entries under a key
+static void process_key(char *key, char *value)
{
- char *fpath;
+ char *path, *pattern = "%s/%s/%s";
- if (!dirtree_notdotdot(dt)) return 0; // Skip . and ..
- if (S_ISDIR(dt->st.st_mode)) return DIRTREE_RECURSE;
- if ((fpath = dirtree_path(dt, 0))) {
- read_key_values(fpath);
- free(fpath);
+ if ((toys.optflags & FLAG_w) && !value && !strchr(key, '=')) {
+ error_msg("'%s' not key=value");
+
+ return;
}
- return 0;
+ path = xmprintf(pattern + 3*!value, "/proc/sys", key, value);
+ value = split_key(path);
+ replace_char(path, '.', '/');
+ // Note: failure to assign to a non-leaf node suppresses the display.
+ if (!(value && (write_key(path, key, value) || (toys.optflags & FLAG_q))))
+ dirtree_read(path, do_show_keys);
+ free(path);
}
void sysctl_main()
{
- char *name = 0, *value = 0, **args = 0;
-
- if (toys.optflags & FLAG_a) {
- dirtree_read(PROC_SYS_DIR, do_flag_a);
- return;
- }
- if (toys.optflags & FLAG_p) {
- if (*toys.optargs) read_config_file(*toys.optargs);
- else read_config_file("/etc/sysctl.conf");
- return;
- }
- if (toys.optflags & FLAG_w) {
- for (args = toys.optargs; *args; args++, name = NULL, value = NULL) {
- parse_key_name_value(*args, &name, &value);
- if (name && value) write_to_file(PROC_SYS_DIR, name, value);
+ char **args = 0;
+
+ // Display all keys
+ if (toys.optflags & FLAG_a) dirtree_read("/proc/sys", do_show_keys);
+
+ // read file
+ else if (toys.optflags & FLAG_p) {
+ FILE *fp = xfopen(*toys.optargs ? *toys.optargs : "/etc/sysctl.conf", "r");
+ char *line = 0;
+ size_t len;
+
+ for (;-1 != (len = getline(&line, &len, fp)); free(line), line = 0) {
+ char *key = line, *val;
+
+ while (isspace(*key)) key++;
+ if (*key == '#' || *key == ';' || !*key) continue;
+ if (!(val = split_key(line))) {
+ error_msg("'%s' not key=value");
+ continue;
+ }
+
+ // Trim whitespace off key and value
+ while (len && isspace(line[len-1])) line[--len] = 0;
+ len = (val-line)-1;
+ while (len && isspace(line[len-1])) line[--len] = 0;
+ while (isspace(*val)) val++;;
+
+ process_key(key, val);
}
- return;
- }
- for (args = toys.optargs; *args; args++) {
- replace_char(*args, '.', '/');
- sprintf(toybuf, "%s/%s", PROC_SYS_DIR, *args);
- read_key_values(toybuf);
- }
+ fclose(fp);
+
+ // Loop through arguments, displaying or assigning as appropriate
+ } else for (args = toys.optargs; *args; args++) process_key(*args, 0);
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-24 03:10:42 +0000