diff options
Diffstat (limited to 'busybox/procps/sysctl.c')
-rw-r--r-- | busybox/procps/sysctl.c | 352 |
1 files changed, 352 insertions, 0 deletions
diff --git a/busybox/procps/sysctl.c b/busybox/procps/sysctl.c new file mode 100644 index 0000000..359dcc0 --- /dev/null +++ b/busybox/procps/sysctl.c @@ -0,0 +1,352 @@ + +/* + * Sysctl 1.01 - A utility to read and manipulate the sysctl parameters + * + * + * "Copyright 1999 George Staikos + * This file may be used subject to the terms and conditions of the + * GNU General Public License Version 2, or any later version + * at your option, as published by the Free Software Foundation. + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details." + * + * Changelog: + * v1.01: + * - added -p <preload> to preload values from a file + * v1.01.1 + * - busybox applet aware by <solar@gentoo.org> + * + */ + +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <sys/stat.h> +#include <sys/types.h> +#include <dirent.h> +#include <string.h> +#include <errno.h> +#include <fcntl.h> +#include "busybox.h" + +/* + * Function Prototypes + */ +static int sysctl_read_setting(const char *setting, int output); +static int sysctl_write_setting(const char *setting, int output); +static int sysctl_preload_file(const char *filename, int output); +static int sysctl_display_all(const char *path, int output, int show_table); + +/* + * Globals... + */ +static const char PROC_PATH[] = "/proc/sys/"; +static const char DEFAULT_PRELOAD[] = "/etc/sysctl.conf"; + +/* error messages */ +static const char ERR_UNKNOWN_PARAMETER[] = "error: Unknown parameter '%s'\n"; +static const char ERR_MALFORMED_SETTING[] = "error: Malformed setting '%s'\n"; +static const char ERR_NO_EQUALS[] = + "error: '%s' must be of the form name=value\n"; +static const char ERR_INVALID_KEY[] = "error: '%s' is an unknown key\n"; +static const char ERR_UNKNOWN_WRITING[] = + "error: unknown error %d setting key '%s'\n"; +static const char ERR_UNKNOWN_READING[] = + "error: unknown error %d reading key '%s'\n"; +static const char ERR_PERMISSION_DENIED[] = + "error: permission denied on key '%s'\n"; +static const char ERR_OPENING_DIR[] = "error: unable to open directory '%s'\n"; +static const char ERR_PRELOAD_FILE[] = + "error: unable to open preload file '%s'\n"; +static const char WARN_BAD_LINE[] = + "warning: %s(%d): invalid syntax, continuing...\n"; + + +static void dwrite_str(int fd, const char *buf) +{ + write(fd, buf, strlen(buf)); +} + +/* + * sysctl_main()... + */ +int sysctl_main(int argc, char **argv) +{ + int retval = 0; + int output = 1; + int write_mode = 0; + int switches_allowed = 1; + + if (argc < 2) + bb_show_usage(); + + argv++; + + for (; argv && *argv && **argv; argv++) { + if (switches_allowed && **argv == '-') { /* we have a switch */ + switch ((*argv)[1]) { + case 'n': + output = 0; + break; + case 'w': + write_mode = 1; + switches_allowed = 0; + break; + case 'p': + argv++; + return + sysctl_preload_file(((argv && *argv + && **argv) ? *argv : + DEFAULT_PRELOAD), output); + case 'a': + case 'A': + switches_allowed = 0; + return sysctl_display_all(PROC_PATH, output, + ((*argv)[1] == 'a') ? 0 : 1); + case 'h': + case '?': + bb_show_usage(); + default: + bb_error_msg(ERR_UNKNOWN_PARAMETER, *argv); + bb_show_usage(); + } + } else { + switches_allowed = 0; + if (write_mode) + retval = sysctl_write_setting(*argv, output); + else + sysctl_read_setting(*argv, output); + } + } + return retval; +} /* end sysctl_main() */ + + + +/* + * sysctl_preload_file + * preload the sysctl's from a conf file + * - we parse the file and then reform it (strip out whitespace) + */ +#define PRELOAD_BUF 256 + +int sysctl_preload_file(const char *filename, int output) +{ + int lineno = 0; + char oneline[PRELOAD_BUF]; + char buffer[PRELOAD_BUF]; + char *name, *value, *ptr; + FILE *fp = NULL; + + if (!filename || ((fp = fopen(filename, "r")) == NULL)) { + bb_error_msg_and_die(ERR_PRELOAD_FILE, filename); + } + + while (fgets(oneline, sizeof(oneline) - 1, fp)) { + oneline[sizeof(oneline) - 1] = 0; + lineno++; + trim(oneline); + ptr = (char *) oneline; + + if (*ptr == '#' || *ptr == ';') + continue; + + if (bb_strlen(ptr) < 2) + continue; + + name = strtok(ptr, "="); + if (!name || !*name) { + bb_error_msg(WARN_BAD_LINE, filename, lineno); + continue; + } + + trim(name); + + value = strtok(NULL, "\n\r"); + if (!value || !*value) { + bb_error_msg(WARN_BAD_LINE, filename, lineno); + continue; + } + + while ((*value == ' ' || *value == '\t') && *value != 0) + value++; + strcpy(buffer, name); + strcat(buffer, "="); + strcat(buffer, value); + sysctl_write_setting(buffer, output); + } + fclose(fp); + return 0; +} /* end sysctl_preload_file() */ + + +/* + * Write a single sysctl setting + */ +int sysctl_write_setting(const char *setting, int output) +{ + int retval = 0; + const char *name = setting; + const char *value; + const char *equals; + char *tmpname, *outname, *cptr; + int fd = -1; + + if (!name) /* probably dont' want to display this err */ + return 0; + + if (!(equals = strchr(setting, '='))) { + bb_error_msg(ERR_NO_EQUALS, setting); + return -1; + } + + value = equals + sizeof(char); /* point to the value in name=value */ + + if (!*name || !*value || name == equals) { + bb_error_msg(ERR_MALFORMED_SETTING, setting); + return -2; + } + + bb_xasprintf(&tmpname, "%s%.*s", PROC_PATH, (equals - name), name); + outname = bb_xstrdup(tmpname + strlen(PROC_PATH)); + + while ((cptr = strchr(tmpname, '.')) != NULL) + *cptr = '/'; + + while ((cptr = strchr(outname, '/')) != NULL) + *cptr = '.'; + + if ((fd = open(tmpname, O_WRONLY | O_CREAT | O_TRUNC, 0666)) < 0) { + switch (errno) { + case ENOENT: + bb_error_msg(ERR_INVALID_KEY, outname); + break; + case EACCES: + bb_perror_msg(ERR_PERMISSION_DENIED, outname); + break; + default: + bb_error_msg(ERR_UNKNOWN_WRITING, errno, outname); + break; + } + retval = -1; + } else { + dwrite_str(fd, value); + close(fd); + if (output) { + dwrite_str(STDOUT_FILENO, outname); + dwrite_str(STDOUT_FILENO, " = "); + } + dwrite_str(STDOUT_FILENO, value); + dwrite_str(STDOUT_FILENO, "\n"); + } + + /* cleanup */ + free(tmpname); + free(outname); + return retval; +} /* end sysctl_write_setting() */ + + +/* + * Read a sysctl setting + * + */ +int sysctl_read_setting(const char *setting, int output) +{ + int retval = 0; + char *tmpname, *outname, *cptr; + char inbuf[1025]; + const char *name = setting; + FILE *fp; + + if (!setting || !*setting) + bb_error_msg(ERR_INVALID_KEY, setting); + + tmpname = concat_path_file(PROC_PATH, name); + outname = bb_xstrdup(tmpname + strlen(PROC_PATH)); + + while ((cptr = strchr(tmpname, '.')) != NULL) + *cptr = '/'; + while ((cptr = strchr(outname, '/')) != NULL) + *cptr = '.'; + + if ((fp = fopen(tmpname, "r")) == NULL) { + switch (errno) { + case ENOENT: + bb_error_msg(ERR_INVALID_KEY, outname); + break; + case EACCES: + bb_error_msg(ERR_PERMISSION_DENIED, outname); + break; + default: + bb_error_msg(ERR_UNKNOWN_READING, errno, outname); + break; + } + retval = -1; + } else { + while (fgets(inbuf, sizeof(inbuf) - 1, fp)) { + if (output) { + dwrite_str(STDOUT_FILENO, outname); + dwrite_str(STDOUT_FILENO, " = "); + } + dwrite_str(STDOUT_FILENO, inbuf); + } + fclose(fp); + } + + free(tmpname); + free(outname); + return retval; +} /* end sysctl_read_setting() */ + + + +/* + * Display all the sysctl settings + * + */ +int sysctl_display_all(const char *path, int output, int show_table) +{ + int retval = 0; + int retval2; + DIR *dp; + struct dirent *de; + char *tmpdir; + struct stat ts; + + if (!(dp = opendir(path))) { + bb_perror_msg(ERR_OPENING_DIR, path); + retval = -1; + } else { + while ((de = readdir(dp)) != NULL) { + tmpdir = concat_subpath_file(path, de->d_name); + if(tmpdir == NULL) + continue; + if ((retval2 = stat(tmpdir, &ts)) != 0) + bb_perror_msg(tmpdir); + else { + if (S_ISDIR(ts.st_mode)) { + sysctl_display_all(tmpdir, output, show_table); + } else + retval |= + sysctl_read_setting(tmpdir + bb_strlen(PROC_PATH), + output); + + } + free(tmpdir); + } /* end while */ + closedir(dp); + } + + return retval; +} /* end sysctl_display_all() */ + +#ifdef STANDALONE_SYSCTL +int main(int argc, char **argv) +{ + return sysctl_main(argc, argv); +} +const char *bb_applet_name = "sysctl"; +#endif |