--- /dev/null
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
+ * Copyright (C) 2006 Rob Landley
+ * Copyright (C) 2006 Denys Vlasenko
+ *
+ * Licensed under GPL version 2, see file LICENSE in this tarball for details.
+ */
+
+/* We need to have separate xfuncs.c and xfuncs_printf.c because
+ * with current linkers, even with section garbage collection,
+ * if *.o module references any of XXXprintf functions, you pull in
+ * entire printf machinery. Even if you do not use the function
+ * which uses XXXprintf.
+ *
+ * xfuncs.c contains functions (not necessarily xfuncs)
+ * which do not pull in printf, directly or indirectly.
+ * xfunc_printf.c contains those which do.
+ */
+
+#include "libbb.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
+/* 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.
+ */
+// Warn if we can't allocate size bytes of memory.
+void *malloc_or_warn(size_t size)
+{
+ void *ptr = malloc(size);
+ if (ptr == NULL && size != 0)
+ bb_error_msg(bb_msg_memory_exhausted);
+ return ptr;
+}
+
+// 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;
+}
+
+// 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 /* DMALLOC */
+
+// Die if we can't allocate and zero size bytes of memory.
+void *xzalloc(size_t size)
+{
+ void *ptr = xmalloc(size);
+ memset(ptr, 0, size);
+ return ptr;
+}
+
+// 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);
+
+ if (t == NULL)
+ bb_error_msg_and_die(bb_msg_memory_exhausted);
+
+ return t;
+}
+
+// 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 (ENABLE_DEBUG && s == NULL)
+ bb_error_msg_and_die("xstrndup bug");
+
+ /* 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 -= m;
+ t = xmalloc(n + 1);
+ t[n] = '\0';
+
+ return memcpy(t, s, n);
+}
+
+// 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 = fopen(path, mode);
+ if (fp == NULL)
+ bb_perror_msg_and_die("can't open '%s'", path);
+ return fp;
+}
+
+// Die if we can't open a file and return a fd.
+int xopen3(const char *pathname, int flags, int mode)
+{
+ int ret;
+
+ ret = open(pathname, flags, mode);
+ if (ret < 0) {
+ bb_perror_msg_and_die("can't open '%s'", pathname);
+ }
+ return ret;
+}
+
+// Die if we can't open an existing file and return a fd.
+int xopen(const char *pathname, int flags)
+{
+ return xopen3(pathname, flags, 0666);
+}
+
+// Warn if we can't open a file and return a fd.
+int open3_or_warn(const char *pathname, int flags, int mode)
+{
+ int ret;
+
+ ret = open(pathname, flags, mode);
+ if (ret < 0) {
+ bb_perror_msg("can't open '%s'", pathname);
+ }
+ return ret;
+}
+
+// Warn if we can't open a file and return a fd.
+int open_or_warn(const char *pathname, int flags)
+{
+ return open3_or_warn(pathname, flags, 0666);
+}
+
+void xunlink(const char *pathname)
+{
+ if (unlink(pathname))
+ bb_perror_msg_and_die("can't remove file '%s'", pathname);
+}
+
+void xrename(const char *oldpath, const char *newpath)
+{
+ if (rename(oldpath, newpath))
+ bb_perror_msg_and_die("can't move '%s' to '%s'", oldpath, newpath);
+}
+
+int rename_or_warn(const char *oldpath, const char *newpath)
+{
+ int n = rename(oldpath, newpath);
+ if (n)
+ bb_perror_msg("can't move '%s' to '%s'", oldpath, newpath);
+ return n;
+}
+
+void xpipe(int filedes[2])
+{
+ if (pipe(filedes))
+ bb_perror_msg_and_die("can't create pipe");
+}
+
+void xdup2(int from, int to)
+{
+ if (dup2(from, to) != to)
+ bb_perror_msg_and_die("can't duplicate file descriptor");
+}
+
+// "Renumber" opened fd
+void xmove_fd(int from, int to)
+{
+ if (from == to)
+ return;
+ xdup2(from, to);
+ close(from);
+}
+
+// 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");
+ }
+}
+
+// Die with an error message if we can't lseek to the right spot.
+off_t xlseek(int fd, off_t offset, int whence)
+{
+ 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;
+}
+
+// Die with supplied filename if this FILE * has ferror set.
+void die_if_ferror(FILE *fp, const char *fn)
+{
+ if (ferror(fp)) {
+ /* ferror doesn't set useful errno */
+ 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);
+ }
+}
+
+
+int bb_putchar(int ch)
+{
+ /* time.c needs putc(ch, stdout), not putchar(ch).
+ * it does "stdout = stderr;", but then glibc's putchar()
+ * doesn't work as expected. bad glibc, bad */
+ return putc(ch, stdout);
+}
+
+/* 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)
+{
+ fflush(stdout);
+ // copyfd outputs error messages for us.
+ if (bb_copyfd_eof(fileno(file), 1) == -1)
+ xfunc_die();
+
+ fclose(file);
+}
+
+// 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
+
+ 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, ...)
+{
+ 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) + 1;
+ va_end(p);
+ string_ptr = malloc(r);
+ if (string_ptr) {
+ va_start(p, format);
+ r = vsnprintf(string_ptr, r, format, p);
+ va_end(p);
+ }
+#endif
+
+ if (r >= 0) {
+ full_write(fd, string_ptr, r);
+ free(string_ptr);
+ }
+ return r;
+}
+#endif
+
+void xsetenv(const char *key, const char *value)
+{
+ if (setenv(key, value, 1))
+ bb_error_msg_and_die(bb_msg_memory_exhausted);
+}
+
+// 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_perror_msg_and_die("setgid");
+}
+
+// Die with an error message if we can't set uid. (See xsetgid() for why.)
+void xsetuid(uid_t uid)
+{
+ if (setuid(uid)) bb_perror_msg_and_die("setuid");
+}
+
+// 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);
+}
+
+void xchroot(const char *path)
+{
+ if (chroot(path))
+ bb_perror_msg_and_die("can't change root directory to %s", path);
+}
+
+// Print a warning message if opendir() fails, but don't die.
+DIR *warn_opendir(const char *path)
+{
+ DIR *dp;
+
+ dp = opendir(path);
+ if (!dp)
+ bb_perror_msg("can't open '%s'", path);
+ return dp;
+}
+
+// Die with an error message if opendir() fails.
+DIR *xopendir(const char *path)
+{
+ DIR *dp;
+
+ dp = opendir(path);
+ if (!dp)
+ bb_perror_msg_and_die("can't open '%s'", path);
+ return dp;
+}
+
+// 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) {
+ /* Hijack vaguely related config option */
+#if ENABLE_VERBOSE_RESOLUTION_ERRORS
+ const char *s = "INET";
+ if (domain == AF_PACKET) s = "PACKET";
+ if (domain == AF_NETLINK) s = "NETLINK";
+USE_FEATURE_IPV6(if (domain == AF_INET6) s = "INET6";)
+ bb_perror_msg_and_die("socket(AF_%s)", s);
+#else
+ bb_perror_msg_and_die("socket");
+#endif
+ }
+
+ 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");
+}
+
+/* Die with an error message if sendto failed.
+ * Return bytes sent otherwise */
+ssize_t xsendto(int s, const void *buf, size_t len, const struct sockaddr *to,
+ socklen_t tolen)
+{
+ ssize_t ret = sendto(s, buf, len, 0, to, tolen);
+ if (ret < 0) {
+ if (ENABLE_FEATURE_CLEAN_UP)
+ close(s);
+ bb_perror_msg_and_die("sendto");
+ }
+ return ret;
+}
+
+// xstat() - a stat() which dies on failure with meaningful error message
+void xstat(const char *name, struct stat *stat_buf)
+{
+ if (stat(name, stat_buf))
+ bb_perror_msg_and_die("can't stat '%s'", name);
+}
+
+// selinux_or_die() - die if SELinux is disabled.
+void selinux_or_die(void)
+{
+#if ENABLE_SELINUX
+ int rc = is_selinux_enabled();
+ if (rc == 0) {
+ bb_error_msg_and_die("SELinux is disabled");
+ } else if (rc < 0) {
+ bb_error_msg_and_die("is_selinux_enabled() failed");
+ }
+#else
+ bb_error_msg_and_die("SELinux support is disabled");
+#endif
+}
+
+int ioctl_or_perror_and_die(int fd, int request, void *argp, const char *fmt,...)
+{
+ int ret;
+ va_list p;
+
+ ret = ioctl(fd, request, argp);
+ if (ret < 0) {
+ va_start(p, fmt);
+ bb_verror_msg(fmt, p, strerror(errno));
+ /* xfunc_die can actually longjmp, so be nice */
+ va_end(p);
+ xfunc_die();
+ }
+ return ret;
+}
+
+int ioctl_or_perror(int fd, int request, void *argp, const char *fmt,...)
+{
+ va_list p;
+ int ret = ioctl(fd, request, argp);
+
+ if (ret < 0) {
+ va_start(p, fmt);
+ bb_verror_msg(fmt, p, strerror(errno));
+ va_end(p);
+ }
+ return ret;
+}
+
+#if ENABLE_IOCTL_HEX2STR_ERROR
+int bb_ioctl_or_warn(int fd, int request, void *argp, const char *ioctl_name)
+{
+ int ret;
+
+ ret = ioctl(fd, request, argp);
+ if (ret < 0)
+ bb_simple_perror_msg(ioctl_name);
+ return ret;
+}
+int bb_xioctl(int fd, int request, void *argp, const char *ioctl_name)
+{
+ int ret;
+
+ ret = ioctl(fd, request, argp);
+ if (ret < 0)
+ bb_simple_perror_msg_and_die(ioctl_name);
+ return ret;
+}
+#else
+int bb_ioctl_or_warn(int fd, int request, void *argp)
+{
+ int ret;
+
+ ret = ioctl(fd, request, argp);
+ if (ret < 0)
+ bb_perror_msg("ioctl %#x failed", request);
+ return ret;
+}
+int bb_xioctl(int fd, int request, void *argp)
+{
+ int ret;
+
+ ret = ioctl(fd, request, argp);
+ if (ret < 0)
+ bb_perror_msg_and_die("ioctl %#x failed", request);
+ return ret;
+}
+#endif
projects / oweals / busybox.git / commitdiff