Correcting branch name to be like previous ones

1 files changed, 521 insertions, 0 deletions

diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c
new file mode 100644
index 000000000..313e32814
--- /dev/null
+++ b/libbb/xfuncs.c
@@ -0,0 +1,521 @@
+/* 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 Denis Vlasenko
+ *
+ * Licensed under GPL version 2, see file LICENSE in this tarball for details.
+ */
+
+#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
+/* 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;
+}
+
+// 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 = 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("%s", path);
+        return fp;
+}
+
+// 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, mode);
+        if (ret < 0) {
+                bb_perror_msg_and_die("%s", pathname);
+        }
+        return ret;
+}
+
+/*
+int ndelay_off(int fd)
+{
+        return fcntl(fd,F_SETFL,fcntl(fd,F_GETFL,0) & ~O_NONBLOCK);
+}
+*/
+// Turn on nonblocking I/O on a fd
+int ndelay_on(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");
+        }
+}
+
+// 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)) {
+                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)
+{
+        static int failed;
+        pid_t pid;
+        void *app = ENABLE_FEATURE_SH_STANDALONE_SHELL ? find_applet_by_name(argv[0]) : 0;
+
+        // Be nice to nommu machines.
+        failed = 0;
+        pid = vfork();
+        if (pid < 0) return pid;
+        if (!pid) {
+                execvp(app ? CONFIG_BUSYBOX_EXEC_PATH : *argv, 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 = -1;
+                _exit(0);
+        }
+        return failed ? failed : 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++;
+                }
+        }
+        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';
+        }
+}
+
+// Convert signed integer to ascii, like utoa_to_buf()
+void itoa_to_buf(int n, char *buf, unsigned buflen)
+{
+        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.
+
+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 local_buf;
+}
+
+// Convert signed integer to ascii using a static buffer (returned).
+char *itoa(int n)
+{
+        itoa_to_buf(n, local_buf, sizeof(local_buf));
+
+        return local_buf;
+}
+
+// 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");
+}
+
+// Die with an error message if we can't set uid.  (See xsetgid() for why.)
+void xsetuid(uid_t uid)
+{
+        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
+
+        if (r < 0) bb_error_msg_and_die(bb_msg_memory_exhausted);
+        return string_ptr;
+}
+
+// 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)
+                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
+
+// 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(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;
+}