* Utility routines.
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ * Copyright (C) 2006 Rob Landley
+ * Copyright (C) 2006 Denis Vlasenko
*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPL version 2, see file LICENSE in this tarball for details.
*/
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include "libbb.h"
+#include "busybox.h"
+/* All the functions starting with "x" call bb_error_msg_and_die() if they
+ * fail, so callers never need to check for errors. If it returned, it
+ * succeeded. */
#ifndef DMALLOC
-#ifdef L_xmalloc
-extern void *xmalloc(size_t size)
+/* dmalloc provides variants of these that do abort() on failure.
+ * Since dmalloc's prototypes overwrite the impls here as they are
+ * included after these prototypes in libbb.h, all is well.
+ */
+// Die if we can't allocate size bytes of memory.
+void *xmalloc(size_t size)
{
void *ptr = malloc(size);
if (ptr == NULL && size != 0)
bb_error_msg_and_die(bb_msg_memory_exhausted);
return ptr;
}
-#endif
-#ifdef L_xrealloc
-extern void *xrealloc(void *ptr, size_t size)
+// Die if we can't resize previously allocated memory. (This returns a pointer
+// to the new memory, which may or may not be the same as the old memory.
+// It'll copy the contents to a new chunk and free the old one if necessary.)
+void *xrealloc(void *ptr, size_t size)
{
ptr = realloc(ptr, size);
if (ptr == NULL && size != 0)
bb_error_msg_and_die(bb_msg_memory_exhausted);
return ptr;
}
-#endif
+#endif /* DMALLOC */
-#ifdef L_xcalloc
-extern void *xcalloc(size_t nmemb, size_t size)
+// Die if we can't allocate and zero size bytes of memory.
+void *xzalloc(size_t size)
{
- void *ptr = calloc(nmemb, size);
- if (ptr == NULL && nmemb != 0 && size != 0)
- bb_error_msg_and_die(bb_msg_memory_exhausted);
+ void *ptr = xmalloc(size);
+ memset(ptr, 0, size);
return ptr;
}
-#endif
-#endif /* DMALLOC */
-#ifdef L_xstrdup
-extern char * bb_xstrdup (const char *s) {
+// Die if we can't copy a string to freshly allocated memory.
+char * xstrdup(const char *s)
+{
char *t;
if (s == NULL)
return NULL;
- t = strdup (s);
+ t = strdup(s);
if (t == NULL)
bb_error_msg_and_die(bb_msg_memory_exhausted);
return t;
}
-#endif
-#ifdef L_xstrndup
-extern char * bb_xstrndup (const char *s, int n) {
+// Die if we can't allocate n+1 bytes (space for the null terminator) and copy
+// the (possibly truncated to length n) string into it.
+char * xstrndup(const char *s, int n)
+{
+ int m;
char *t;
- if (s == NULL)
- bb_error_msg_and_die("bb_xstrndup bug");
+ if (ENABLE_DEBUG && s == NULL)
+ bb_error_msg_and_die("xstrndup bug");
- t = xmalloc(++n);
+ /* We can just xmalloc(n+1) and strncpy into it, */
+ /* but think about xstrndup("abc", 10000) wastage! */
+ m = n;
+ t = (char*) s;
+ while (m) {
+ if (!*t) break;
+ m--; t++;
+ }
+ n = n - m;
+ t = xmalloc(n + 1);
+ t[n] = '\0';
- return safe_strncpy(t,s,n);
+ return memcpy(t,s,n);
}
-#endif
-#ifdef L_xfopen
-FILE *bb_xfopen(const char *path, const char *mode)
+// Die if we can't open a file and return a FILE * to it.
+// Notice we haven't got xfread(), This is for use with fscanf() and friends.
+FILE *xfopen(const char *path, const char *mode)
{
- FILE *fp;
- if ((fp = fopen(path, mode)) == NULL)
+ FILE *fp = fopen(path, mode);
+ if (fp == NULL)
bb_perror_msg_and_die("%s", path);
return fp;
}
-#endif
-#ifdef L_xopen
-extern int bb_xopen(const char *pathname, int flags)
+// Die if we can't open an existing file and return an fd.
+int xopen(const char *pathname, int flags)
+{
+ //if (ENABLE_DEBUG && (flags & O_CREAT))
+ // bb_error_msg_and_die("xopen() with O_CREAT");
+
+ return xopen3(pathname, flags, 0666);
+}
+
+// Die if we can't open a new file and return an fd.
+int xopen3(const char *pathname, int flags, int mode)
{
int ret;
- ret = open(pathname, flags, 0777);
- if (ret == -1) {
+ ret = open(pathname, flags, mode);
+ if (ret < 0) {
bb_perror_msg_and_die("%s", pathname);
}
return ret;
}
-#endif
-#ifdef L_xread
-extern ssize_t bb_xread(int fd, void *buf, size_t count)
+// Turn on nonblocking I/O on a fd
+int ndelay_on(int fd)
{
- ssize_t size;
+ return fcntl(fd,F_SETFL,fcntl(fd,F_GETFL,0) | O_NONBLOCK);
+}
- size = read(fd, buf, count);
- if (size == -1) {
- bb_perror_msg_and_die(bb_msg_read_error);
+int ndelay_off(int fd)
+{
+ return fcntl(fd,F_SETFL,fcntl(fd,F_GETFL,0) & ~O_NONBLOCK);
+}
+
+// Die with an error message if we can't write the entire buffer.
+void xwrite(int fd, const void *buf, size_t count)
+{
+ if (count) {
+ ssize_t size = full_write(fd, buf, count);
+ if (size != count)
+ bb_error_msg_and_die("short write");
}
- return(size);
}
-#endif
-#ifdef L_xread_all
-extern void bb_xread_all(int fd, void *buf, size_t count)
+// Die with an error message if we can't lseek to the right spot.
+off_t xlseek(int fd, off_t offset, int whence)
{
- ssize_t size;
+ off_t off = lseek(fd, offset, whence);
+ if (off == (off_t)-1) {
+ if (whence == SEEK_SET)
+ bb_perror_msg_and_die("lseek(%"OFF_FMT"u)", offset);
+ bb_perror_msg_and_die("lseek");
+ }
+ return off;
+}
- while (count) {
- if ((size = bb_xread(fd, buf, count)) == 0) { /* EOF */
- bb_error_msg_and_die("Short read");
+// Die with supplied filename if this FILE * has ferror set.
+void die_if_ferror(FILE *fp, const char *fn)
+{
+ if (ferror(fp)) {
+ bb_error_msg_and_die("%s: I/O error", fn);
+ }
+}
+
+// Die with an error message if stdout has ferror set.
+void die_if_ferror_stdout(void)
+{
+ die_if_ferror(stdout, bb_msg_standard_output);
+}
+
+// Die with an error message if we have trouble flushing stdout.
+void xfflush_stdout(void)
+{
+ if (fflush(stdout)) {
+ bb_perror_msg_and_die(bb_msg_standard_output);
+ }
+}
+
+// This does a fork/exec in one call, using vfork(). Return PID of new child,
+// -1 for failure. Runs argv[0], searching path if that has no / in it.
+pid_t spawn(char **argv)
+{
+ /* Why static? */
+ static int failed;
+ pid_t pid;
+ char *prog;
+
+ // Be nice to nommu machines.
+ failed = 0;
+ pid = vfork();
+ if (pid < 0) return pid;
+ if (!pid) {
+ prog = argv[0];
+ if (ENABLE_FEATURE_EXEC_PREFER_APPLETS && find_applet_by_name(prog))
+ prog = CONFIG_BUSYBOX_EXEC_PATH;
+ execvp(prog, argv);
+
+ // We're sharing a stack with blocked parent, let parent know we failed
+ // and then exit to unblock parent (but don't run atexit() stuff, which
+ // would screw up parent.)
+
+ failed = errno;
+ _exit(0);
+ }
+ if (failed) {
+ errno = failed;
+ return -1;
+ }
+ return pid;
+}
+
+// Die with an error message if we can't spawn a child process.
+pid_t xspawn(char **argv)
+{
+ pid_t pid = spawn(argv);
+ if (pid < 0) bb_perror_msg_and_die("%s", *argv);
+ return pid;
+}
+
+// Wait for the specified child PID to exit, returning child's error return.
+int wait4pid(int pid)
+{
+ int status;
+
+ if (pid == -1 || waitpid(pid, &status, 0) == -1) return -1;
+ if (WIFEXITED(status)) return WEXITSTATUS(status);
+ if (WIFSIGNALED(status)) return WTERMSIG(status);
+ return 0;
+}
+
+void xsetenv(const char *key, const char *value)
+{
+ if (setenv(key, value, 1))
+ bb_error_msg_and_die(bb_msg_memory_exhausted);
+}
+
+// Converts unsigned long long value into compact 4-char
+// representation. Examples: "1234", "1.2k", " 27M", "123T"
+// Fifth char is always '\0'
+void smart_ulltoa5(unsigned long long ul, char buf[5])
+{
+ char *fmt;
+ char c;
+ unsigned v,idx = 0;
+ ul *= 10;
+ if (ul > 9999*10) { // do not scale if 9999 or less
+ while (ul >= 10000) {
+ ul /= 1024;
+ idx++;
}
- count -= size;
- buf = ((char *) buf) + size;
}
- return;
+ v = ul; // ullong divisions are expensive, avoid them
+
+ fmt = " 123456789";
+ if (!idx) { // 9999 or less: use 1234 format
+ c = buf[0] = " 123456789"[v/10000];
+ if (c!=' ') fmt = "0123456789";
+ c = buf[1] = fmt[v/1000%10];
+ if (c!=' ') fmt = "0123456789";
+ buf[2] = fmt[v/100%10];
+ buf[3] = "0123456789"[v/10%10];
+ } else {
+ if (v>=10*10) { // scaled value is >=10: use 123M format
+ c = buf[0] = " 123456789"[v/1000];
+ if (c!=' ') fmt = "0123456789";
+ buf[1] = fmt[v/100%10];
+ buf[2] = "0123456789"[v/10%10];
+ } else { // scaled value is <10: use 1.2M format
+ buf[0] = "0123456789"[v/10];
+ buf[1] = '.';
+ buf[2] = "0123456789"[v%10];
+ }
+ // see http://en.wikipedia.org/wiki/Tera
+ buf[3] = " kMGTPEZY"[idx];
+ }
+ buf[4] = '\0';
+}
+
+// Convert unsigned integer to ascii, writing into supplied buffer. A
+// truncated result is always null terminated (unless buflen is 0), and
+// contains the first few digits of the result ala strncpy.
+void BUG_sizeof_unsigned_not_4(void);
+void utoa_to_buf(unsigned n, char *buf, unsigned buflen)
+{
+ unsigned i, out, res;
+ if (sizeof(unsigned) != 4)
+ BUG_sizeof_unsigned_not_4();
+ if (buflen) {
+ out = 0;
+ for (i = 1000000000; i; i /= 10) {
+ res = n / i;
+ if (res || out || i == 1) {
+ if (!--buflen) break;
+ out++;
+ n -= res*i;
+ *buf++ = '0' + res;
+ }
+ }
+ *buf = '\0';
+ }
}
-#endif
-#ifdef L_xread_char
-extern unsigned char bb_xread_char(int fd)
+// Convert signed integer to ascii, like utoa_to_buf()
+void itoa_to_buf(int n, char *buf, unsigned buflen)
{
- char tmp;
+ if (buflen && n<0) {
+ n = -n;
+ *buf++ = '-';
+ buflen--;
+ }
+ utoa_to_buf((unsigned)n, buf, buflen);
+}
+
+// The following two functions use a static buffer, so calling either one a
+// second time will overwrite previous results.
+//
+// The largest 32 bit integer is -2 billion plus null terminator, or 12 bytes.
+// Int should always be 32 bits on any remotely Unix-like system, see
+// http://www.unix.org/whitepapers/64bit.html for the reasons why.
- bb_xread_all(fd, &tmp, 1);
+static char local_buf[12];
+
+// Convert unsigned integer to ascii using a static buffer (returned).
+char *utoa(unsigned n)
+{
+ utoa_to_buf(n, local_buf, sizeof(local_buf));
- return(tmp);
+ return local_buf;
}
-#endif
-#ifdef L_xferror
-extern void bb_xferror(FILE *fp, const char *fn)
+// Convert signed integer to ascii using a static buffer (returned).
+char *itoa(int n)
{
- if (ferror(fp)) {
- bb_error_msg_and_die("%s", fn);
+ itoa_to_buf(n, local_buf, sizeof(local_buf));
+
+ return local_buf;
+}
+
+// Emit a string of hex representation of bytes
+char *bin2hex(char *p, const char *cp, int count)
+{
+ while (count) {
+ unsigned char c = *cp++;
+ /* put lowercase hex digits */
+ *p++ = 0x10 | bb_hexdigits_upcase[c >> 4];
+ *p++ = 0x10 | bb_hexdigits_upcase[c & 0xf];
+ count--;
}
+ return p;
+}
+
+// Die with an error message if we can't set gid. (Because resource limits may
+// limit this user to a given number of processes, and if that fills up the
+// setgid() will fail and we'll _still_be_root_, which is bad.)
+void xsetgid(gid_t gid)
+{
+ if (setgid(gid)) bb_error_msg_and_die("setgid");
}
-#endif
-#ifdef L_xferror_stdout
-extern void bb_xferror_stdout(void)
+// Die with an error message if we can't set uid. (See xsetgid() for why.)
+void xsetuid(uid_t uid)
{
- bb_xferror(stdout, bb_msg_standard_output);
+ if (setuid(uid)) bb_error_msg_and_die("setuid");
+}
+
+// Return how long the file at fd is, if there's any way to determine it.
+off_t fdlength(int fd)
+{
+ off_t bottom = 0, top = 0, pos;
+ long size;
+
+ // If the ioctl works for this, return it.
+
+ if (ioctl(fd, BLKGETSIZE, &size) >= 0) return size*512;
+
+ // FIXME: explain why lseek(SEEK_END) is not used here!
+
+ // If not, do a binary search for the last location we can read. (Some
+ // block devices don't do BLKGETSIZE right.)
+
+ do {
+ char temp;
+
+ pos = bottom + (top - bottom) / 2;
+
+ // If we can read from the current location, it's bigger.
+
+ if (lseek(fd, pos, SEEK_SET)>=0 && safe_read(fd, &temp, 1)==1) {
+ if (bottom == top) bottom = top = (top+1) * 2;
+ else bottom = pos;
+
+ // If we can't, it's smaller.
+
+ } else {
+ if (bottom == top) {
+ if (!top) return 0;
+ bottom = top/2;
+ }
+ else top = pos;
+ }
+ } while (bottom + 1 != top);
+
+ return pos + 1;
}
+
+// Die with an error message if we can't malloc() enough space and do an
+// sprintf() into that space.
+char *xasprintf(const char *format, ...)
+{
+ va_list p;
+ int r;
+ char *string_ptr;
+
+#if 1
+ // GNU extension
+ va_start(p, format);
+ r = vasprintf(&string_ptr, format, p);
+ va_end(p);
+#else
+ // Bloat for systems that haven't got the GNU extension.
+ va_start(p, format);
+ r = vsnprintf(NULL, 0, format, p);
+ va_end(p);
+ string_ptr = xmalloc(r+1);
+ va_start(p, format);
+ r = vsnprintf(string_ptr, r+1, format, p);
+ va_end(p);
#endif
-#ifdef L_xfflush_stdout
-extern void bb_xfflush_stdout(void)
+ if (r < 0) bb_error_msg_and_die(bb_msg_memory_exhausted);
+ return string_ptr;
+}
+
+#if 0 /* If we will ever meet a libc which hasn't [f]dprintf... */
+int fdprintf(int fd, const char *format, ...)
{
- if (fflush(stdout)) {
- bb_perror_msg_and_die(bb_msg_standard_output);
+ va_list p;
+ int r;
+ char *string_ptr;
+
+#if 1
+ // GNU extension
+ va_start(p, format);
+ r = vasprintf(&string_ptr, format, p);
+ va_end(p);
+#else
+ // Bloat for systems that haven't got the GNU extension.
+ va_start(p, format);
+ r = vsnprintf(NULL, 0, format, p);
+ va_end(p);
+ string_ptr = xmalloc(r+1);
+ va_start(p, format);
+ r = vsnprintf(string_ptr, r+1, format, p);
+ va_end(p);
+#endif
+
+ if (r >= 0) {
+ full_write(fd, string_ptr, r);
+ free(string_ptr);
}
+ return r;
}
#endif
-#ifdef L_strlen
-/* Since gcc always inlines strlen(), this saves a byte or two, but we need
- * the #undef here to avoid endless loop from #define strlen bb_strlen */
-#undef strlen
-size_t bb_strlen(const char *string)
+// Die with an error message if we can't copy an entire FILE * to stdout, then
+// close that file.
+void xprint_and_close_file(FILE *file)
{
- return(strlen(string));
+ fflush(stdout);
+ // copyfd outputs error messages for us.
+ if (bb_copyfd_eof(fileno(file), 1) == -1)
+ exit(xfunc_error_retval);
+
+ fclose(file);
+}
+
+// Die if we can't chdir to a new path.
+void xchdir(const char *path)
+{
+ if (chdir(path))
+ bb_perror_msg_and_die("chdir(%s)", path);
+}
+
+// Print a warning message if opendir() fails, but don't die.
+DIR *warn_opendir(const char *path)
+{
+ DIR *dp;
+
+ if ((dp = opendir(path)) == NULL) {
+ bb_perror_msg("cannot open '%s'", path);
+ return NULL;
+ }
+ return dp;
+}
+
+// Die with an error message if opendir() fails.
+DIR *xopendir(const char *path)
+{
+ DIR *dp;
+
+ if ((dp = opendir(path)) == NULL)
+ bb_perror_msg_and_die("cannot open '%s'", path);
+ return dp;
+}
+
+#ifndef BB_NOMMU
+// Die with an error message if we can't daemonize.
+void xdaemon(int nochdir, int noclose)
+{
+ if (daemon(nochdir, noclose))
+ bb_perror_msg_and_die("daemon");
}
#endif
-/* END CODE */
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
+void bb_sanitize_stdio_maybe_daemonize(int daemonize)
+{
+ int fd;
+ /* Mega-paranoid */
+ fd = xopen(bb_dev_null, O_RDWR);
+ while (fd < 2)
+ fd = dup(fd); /* have 0,1,2 open at least to /dev/null */
+ if (daemonize) {
+ pid_t pid = fork();
+ if (pid < 0) /* wtf? */
+ bb_perror_msg_and_die("fork");
+ if (pid) /* parent */
+ exit(0);
+ /* child */
+ /* if daemonizing, make sure we detach from stdio */
+ setsid();
+ dup2(fd, 0);
+ dup2(fd, 1);
+ dup2(fd, 2);
+ }
+ while (fd > 2)
+ close(fd--); /* close everything after fd#2 */
+}
+void bb_sanitize_stdio(void)
+{
+ bb_sanitize_stdio_maybe_daemonize(0);
+}
+void bb_daemonize(void)
+{
+ bb_sanitize_stdio_maybe_daemonize(1);
+}
+
+// Die with an error message if we can't open a new socket.
+int xsocket(int domain, int type, int protocol)
+{
+ int r = socket(domain, type, protocol);
+
+ if (r < 0) bb_perror_msg_and_die("socket");
+
+ return r;
+}
+
+// Die with an error message if we can't bind a socket to an address.
+void xbind(int sockfd, struct sockaddr *my_addr, socklen_t addrlen)
+{
+ if (bind(sockfd, my_addr, addrlen)) bb_perror_msg_and_die("bind");
+}
+
+// Die with an error message if we can't listen for connections on a socket.
+void xlisten(int s, int backlog)
+{
+ if (listen(s, backlog)) bb_perror_msg_and_die("listen");
+}
+
+// xstat() - a stat() which dies on failure with meaningful error message
+void xstat(char *name, struct stat *stat_buf)
+{
+ if (stat(name, stat_buf))
+ bb_perror_msg_and_die("can't stat '%s'", name);
+}
+
+/* It is perfectly ok to pass in a NULL for either width or for
+ * height, in which case that value will not be set. */
+int get_terminal_width_height(const int fd, int *width, int *height)
+{
+ struct winsize win = { 0, 0, 0, 0 };
+ int ret = ioctl(fd, TIOCGWINSZ, &win);
+
+ if (height) {
+ if (!win.ws_row) {
+ char *s = getenv("LINES");
+ if (s) win.ws_row = atoi(s);
+ }
+ if (win.ws_row <= 1 || win.ws_row >= 30000)
+ win.ws_row = 24;
+ *height = (int) win.ws_row;
+ }
+
+ if (width) {
+ if (!win.ws_col) {
+ char *s = getenv("COLUMNS");
+ if (s) win.ws_col = atoi(s);
+ }
+ if (win.ws_col <= 1 || win.ws_col >= 30000)
+ win.ws_col = 80;
+ *width = (int) win.ws_col;
+ }
+
+ return ret;
+}
projects / oweals / busybox.git / blobdiff