openwrt/package/nvram/src/shutils.c

330 lines
7.1 KiB
C

/*
* Shell-like utility functions
*
* Copyright 2004, Broadcom Corporation
* All Rights Reserved.
*
* THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
* KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
* SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
*
* $Id$
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <errno.h>
#include <error.h>
#include <fcntl.h>
#include <limits.h>
#include <unistd.h>
#include <signal.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <termios.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <net/ethernet.h>
#include <shutils.h>
/*
* Reads file and returns contents
* @param fd file descriptor
* @return contents of file or NULL if an error occurred
*/
char *
fd2str(int fd)
{
char *buf = NULL;
size_t count = 0, n;
do {
buf = realloc(buf, count + 512);
n = read(fd, buf + count, 512);
if (n < 0) {
free(buf);
buf = NULL;
}
count += n;
} while (n == 512);
close(fd);
if (buf)
buf[count] = '\0';
return buf;
}
/*
* Reads file and returns contents
* @param path path to file
* @return contents of file or NULL if an error occurred
*/
char *
file2str(const char *path)
{
int fd;
if ((fd = open(path, O_RDONLY)) == -1) {
perror(path);
return NULL;
}
return fd2str(fd);
}
/*
* Waits for a file descriptor to change status or unblocked signal
* @param fd file descriptor
* @param timeout seconds to wait before timing out or 0 for no timeout
* @return 1 if descriptor changed status or 0 if timed out or -1 on error
*/
int
waitfor(int fd, int timeout)
{
fd_set rfds;
struct timeval tv = { timeout, 0 };
FD_ZERO(&rfds);
FD_SET(fd, &rfds);
return select(fd + 1, &rfds, NULL, NULL, (timeout > 0) ? &tv : NULL);
}
/*
* Concatenates NULL-terminated list of arguments into a single
* commmand and executes it
* @param argv argument list
* @param path NULL, ">output", or ">>output"
* @param timeout seconds to wait before timing out or 0 for no timeout
* @param ppid NULL to wait for child termination or pointer to pid
* @return return value of executed command or errno
*/
int
_eval(char *const argv[], char *path, int timeout, int *ppid)
{
pid_t pid;
int status;
int fd;
int flags;
int sig;
char buf[254]="";
int i;
switch (pid = fork()) {
case -1: /* error */
perror("fork");
return errno;
case 0: /* child */
/* Reset signal handlers set for parent process */
for (sig = 0; sig < (_NSIG-1); sig++)
signal(sig, SIG_DFL);
/* Clean up */
ioctl(0, TIOCNOTTY, 0);
close(STDIN_FILENO);
close(STDOUT_FILENO);
close(STDERR_FILENO);
setsid();
/* We want to check the board if exist UART? , add by honor 2003-12-04 */
if ((fd = open("/dev/console", O_RDWR)) < 0) {
(void) open("/dev/null", O_RDONLY);
(void) open("/dev/null", O_WRONLY);
(void) open("/dev/null", O_WRONLY);
}
else{
close(fd);
(void) open("/dev/console", O_RDONLY);
(void) open("/dev/console", O_WRONLY);
(void) open("/dev/console", O_WRONLY);
}
/* Redirect stdout to <path> */
if (path) {
flags = O_WRONLY | O_CREAT;
if (!strncmp(path, ">>", 2)) {
/* append to <path> */
flags |= O_APPEND;
path += 2;
} else if (!strncmp(path, ">", 1)) {
/* overwrite <path> */
flags |= O_TRUNC;
path += 1;
}
if ((fd = open(path, flags, 0644)) < 0)
perror(path);
else {
dup2(fd, STDOUT_FILENO);
close(fd);
}
}
/* execute command */
for(i=0 ; argv[i] ; i++)
snprintf(buf+strlen(buf), sizeof(buf), "%s ", argv[i]);
dprintf("cmd=[%s]\n", buf);
setenv("PATH", "/sbin:/bin:/usr/sbin:/usr/bin", 1);
alarm(timeout);
execvp(argv[0], argv);
perror(argv[0]);
exit(errno);
default: /* parent */
if (ppid) {
*ppid = pid;
return 0;
} else {
waitpid(pid, &status, 0);
if (WIFEXITED(status))
return WEXITSTATUS(status);
else
return status;
}
}
}
/*
* Concatenates NULL-terminated list of arguments into a single
* commmand and executes it
* @param argv argument list
* @return stdout of executed command or NULL if an error occurred
*/
char *
_backtick(char *const argv[])
{
int filedes[2];
pid_t pid;
int status;
char *buf = NULL;
/* create pipe */
if (pipe(filedes) == -1) {
perror(argv[0]);
return NULL;
}
switch (pid = fork()) {
case -1: /* error */
return NULL;
case 0: /* child */
close(filedes[0]); /* close read end of pipe */
dup2(filedes[1], 1); /* redirect stdout to write end of pipe */
close(filedes[1]); /* close write end of pipe */
execvp(argv[0], argv);
exit(errno);
break;
default: /* parent */
close(filedes[1]); /* close write end of pipe */
buf = fd2str(filedes[0]);
waitpid(pid, &status, 0);
break;
}
return buf;
}
/*
* Kills process whose PID is stored in plaintext in pidfile
* @param pidfile PID file
* @return 0 on success and errno on failure
*/
int
kill_pidfile(char *pidfile)
{
FILE *fp = fopen(pidfile, "r");
char buf[256];
if (fp && fgets(buf, sizeof(buf), fp)) {
pid_t pid = strtoul(buf, NULL, 0);
fclose(fp);
return kill(pid, SIGTERM);
} else
return errno;
}
/*
* fread() with automatic retry on syscall interrupt
* @param ptr location to store to
* @param size size of each element of data
* @param nmemb number of elements
* @param stream file stream
* @return number of items successfully read
*/
int
safe_fread(void *ptr, size_t size, size_t nmemb, FILE *stream)
{
size_t ret = 0;
do {
clearerr(stream);
ret += fread((char *)ptr + (ret * size), size, nmemb - ret, stream);
} while (ret < nmemb && ferror(stream) && errno == EINTR);
return ret;
}
/*
* fwrite() with automatic retry on syscall interrupt
* @param ptr location to read from
* @param size size of each element of data
* @param nmemb number of elements
* @param stream file stream
* @return number of items successfully written
*/
int
safe_fwrite(const void *ptr, size_t size, size_t nmemb, FILE *stream)
{
size_t ret = 0;
do {
clearerr(stream);
ret += fwrite((char *)ptr + (ret * size), size, nmemb - ret, stream);
} while (ret < nmemb && ferror(stream) && errno == EINTR);
return ret;
}
/*
* Convert Ethernet address string representation to binary data
* @param a string in xx:xx:xx:xx:xx:xx notation
* @param e binary data
* @return TRUE if conversion was successful and FALSE otherwise
*/
int
ether_atoe(const char *a, unsigned char *e)
{
char *c = (char *) a;
int i = 0;
memset(e, 0, ETHER_ADDR_LEN);
for (;;) {
e[i++] = (unsigned char) strtoul(c, &c, 16);
if (!*c++ || i == ETHER_ADDR_LEN)
break;
}
return (i == ETHER_ADDR_LEN);
}
/*
* Convert Ethernet address binary data to string representation
* @param e binary data
* @param a string in xx:xx:xx:xx:xx:xx notation
* @return a
*/
char *
ether_etoa(const unsigned char *e, char *a)
{
char *c = a;
int i;
for (i = 0; i < ETHER_ADDR_LEN; i++) {
if (i)
*c++ = ':';
c += sprintf(c, "%02X", e[i] & 0xff);
}
return a;
}