bc: convert to "G trick" - this returns bc to zero bss increase
[oweals/busybox.git] / coreutils / cp.c
index 078a57c565b799ca8496f738a80c7b5df0f70295..b26c0e9547c8a45a2f01ec15d6a79dfd1a984853 100644 (file)
-#include "internal.h"
-#include <stdio.h>
-#include <sys/stat.h>
-#include <sys/fcntl.h>
-#include <sys/param.h>
-#include <errno.h>
+/* vi: set sw=4 ts=4: */
+/*
+ * Mini cp implementation for busybox
+ *
+ * Copyright (C) 2000 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
+ * SELinux support by Yuichi Nakamura <ynakam@hitachisoft.jp>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+/* Mar 16, 2003      Manuel Novoa III   (mjn3@codepoet.org)
+ *
+ * Size reduction.
+ */
+//config:config CP
+//config:      bool "cp (9.7 kb)"
+//config:      default y
+//config:      help
+//config:      cp is used to copy files and directories.
+//config:
+//config:config FEATURE_CP_LONG_OPTIONS
+//config:      bool "Enable long options"
+//config:      default y
+//config:      depends on CP && LONG_OPTS
+//config:      help
+//config:      Enable long options.
+//config:      Also add support for --parents option.
+//config:
+//config:config FEATURE_CP_REFLINK
+//config:      bool "Enable --reflink[=auto]"
+//config:      default y
+//config:      depends on FEATURE_CP_LONG_OPTIONS
 
-const char  cp_usage[] = "cp [-r] source-file destination-file\n"
-"\t\tcp [-r] source-file [source-file ...] destination-directory\n"
-"\n"
-"\tCopy the source files to the destination.\n"
-"\n"
-"\t-r:\tRecursively copy all files and directories\n"
-"\t\tunder the argument directory.";
+//applet:IF_CP(APPLET_NOEXEC(cp, cp, BB_DIR_BIN, BB_SUID_DROP, cp))
+/* NOEXEC despite cases when it can be a "runner" (cp -r LARGE_DIR NEW_DIR) */
 
-extern int
-cp_fn(const struct FileInfo * i)
+//kbuild:lib-$(CONFIG_CP) += cp.o
+
+/* http://www.opengroup.org/onlinepubs/007904975/utilities/cp.html */
+
+//usage:#define cp_trivial_usage
+//usage:       "[OPTIONS] SOURCE... DEST"
+//usage:#define cp_full_usage "\n\n"
+//usage:       "Copy SOURCE(s) to DEST\n"
+//usage:     "\n       -a      Same as -dpR"
+//usage:       IF_SELINUX(
+//usage:     "\n       -c      Preserve security context"
+//usage:       )
+//usage:     "\n       -R,-r   Recurse"
+//usage:     "\n       -d,-P   Preserve symlinks (default if -R)"
+//usage:     "\n       -L      Follow all symlinks"
+//usage:     "\n       -H      Follow symlinks on command line"
+//usage:     "\n       -p      Preserve file attributes if possible"
+//usage:     "\n       -f      Overwrite"
+//usage:     "\n       -i      Prompt before overwrite"
+//usage:     "\n       -l,-s   Create (sym)links"
+//usage:     "\n       -T      Treat DEST as a normal file"
+//usage:     "\n       -u      Copy only newer files"
+
+#include "libbb.h"
+#include "libcoreutils/coreutils.h"
+
+/* This is a NOEXEC applet. Be very careful! */
+
+int cp_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int cp_main(int argc, char **argv)
 {
-    int         sourceFd;
-    int         destinationFd;
-    const char * destination = i->destination;
-    struct stat destination_stat;
-    int         status;
-    char        buf[8192];
-    char        d[PATH_MAX];
+       struct stat source_stat;
+       struct stat dest_stat;
+       const char *last;
+       const char *dest;
+       int s_flags;
+       int d_flags;
+       int flags;
+       int status;
+       enum {
+               FILEUTILS_CP_OPTNUM = sizeof(FILEUTILS_CP_OPTSTR)-1,
+#if ENABLE_FEATURE_CP_LONG_OPTIONS
+               /*OPT_rmdest  = FILEUTILS_RMDEST = 1 << FILEUTILS_CP_OPTNUM */
+               OPT_parents = 1 << (FILEUTILS_CP_OPTNUM+1),
+               OPT_reflink = 1 << (FILEUTILS_CP_OPTNUM+2),
+#endif
+       };
+
+#if ENABLE_FEATURE_CP_LONG_OPTIONS
+# if ENABLE_FEATURE_CP_REFLINK
+       char *reflink = NULL;
+# endif
+       flags = getopt32long(argv, "^"
+               FILEUTILS_CP_OPTSTR
+               "\0"
+               // Need at least two arguments
+               // Soft- and hardlinking doesn't mix
+               // -P and -d are the same (-P is POSIX, -d is GNU)
+               // -r and -R are the same
+               // -R (and therefore -r) turns on -d (coreutils does this)
+               // -a = -pdR
+               "-2:l--s:s--l:Pd:rRd:Rd:apdR",
+               "archive\0"        No_argument "a"
+               "force\0"          No_argument "f"
+               "interactive\0"    No_argument "i"
+               "link\0"           No_argument "l"
+               "dereference\0"    No_argument "L"
+               "no-dereference\0" No_argument "P"
+               "recursive\0"      No_argument "R"
+               "symbolic-link\0"  No_argument "s"
+               "no-target-directory\0" No_argument "T"
+               "verbose\0"        No_argument "v"
+               "update\0"         No_argument "u"
+               "remove-destination\0" No_argument "\xff"
+               "parents\0"        No_argument "\xfe"
+# if ENABLE_FEATURE_CP_REFLINK
+               "reflink\0"        Optional_argument "\xfd"
+               , &reflink
+# endif
+       );
+# if ENABLE_FEATURE_CP_REFLINK
+       BUILD_BUG_ON((int)OPT_reflink != (int)FILEUTILS_REFLINK);
+       if (flags & FILEUTILS_REFLINK) {
+               if (!reflink)
+                       flags |= FILEUTILS_REFLINK_ALWAYS;
+               else if (strcmp(reflink, "always") == 0)
+                       flags |= FILEUTILS_REFLINK_ALWAYS;
+               else if (strcmp(reflink, "auto") != 0)
+                       bb_show_usage();
+       }
+# endif
+#else
+       flags = getopt32(argv, "^"
+               FILEUTILS_CP_OPTSTR
+               "\0"
+               "-2:l--s:s--l:Pd:rRd:Rd:apdR"
+       );
+#endif
+       /* Options of cp from GNU coreutils 6.10:
+        * -a, --archive
+        * -f, --force
+        * -i, --interactive
+        * -l, --link
+        * -L, --dereference
+        * -P, --no-dereference
+        * -R, -r, --recursive
+        * -s, --symbolic-link
+        * -v, --verbose
+        * -H   follow command-line symbolic links in SOURCE
+        * -d   same as --no-dereference --preserve=links
+        * -p   same as --preserve=mode,ownership,timestamps
+        * -c   same as --preserve=context
+        * -u, --update
+        *      copy only when the SOURCE file is newer than the destination
+        *      file or when the destination file is missing
+        * --remove-destination
+        *      remove each existing destination file before attempting to open
+        * --parents
+        *      use full source file name under DIRECTORY
+        * -T, --no-target-directory
+        *      treat DEST as a normal file
+        * NOT SUPPORTED IN BBOX:
+        * --backup[=CONTROL]
+        *      make a backup of each existing destination file
+        * -b   like --backup but does not accept an argument
+        * --copy-contents
+        *      copy contents of special files when recursive
+        * --preserve[=ATTR_LIST]
+        *      preserve attributes (default: mode,ownership,timestamps),
+        *      if possible additional attributes: security context,links,all
+        * --no-preserve=ATTR_LIST
+        * --sparse=WHEN
+        *      control creation of sparse files
+        * --strip-trailing-slashes
+        *      remove any trailing slashes from each SOURCE argument
+        * -S, --suffix=SUFFIX
+        *      override the usual backup suffix
+        * -t, --target-directory=DIRECTORY
+        *      copy all SOURCE arguments into DIRECTORY
+        * -x, --one-file-system
+        *      stay on this file system
+        * -Z, --context=CONTEXT
+        *      (SELinux) set SELinux security context of copy to CONTEXT
+        */
+       argc -= optind;
+       argv += optind;
+       /* Reverse this bit. If there is -d, bit is not set: */
+       flags ^= FILEUTILS_DEREFERENCE;
+       /* coreutils 6.9 compat:
+        * by default, "cp" derefs symlinks (creates regular dest files),
+        * but "cp -R" does not. We switch off deref if -r or -R (see above).
+        * However, "cp -RL" must still deref symlinks: */
+       if (flags & FILEUTILS_DEREF_SOFTLINK) /* -L */
+               flags |= FILEUTILS_DEREFERENCE;
+
+#if ENABLE_SELINUX
+       if (flags & FILEUTILS_PRESERVE_SECURITY_CONTEXT) {
+               selinux_or_die();
+       }
+#endif
+
+       status = EXIT_SUCCESS;
+       last = argv[argc - 1];
+       /* If there are only two arguments and...  */
+       if (argc == 2) {
+               s_flags = cp_mv_stat2(*argv, &source_stat,
+                               (flags & FILEUTILS_DEREFERENCE) ? stat : lstat);
+               if (s_flags < 0)
+                       return EXIT_FAILURE;
+               d_flags = cp_mv_stat(last, &dest_stat);
+               if (d_flags < 0)
+                       return EXIT_FAILURE;
+
+               if (flags & FILEUTILS_NO_TARGET_DIR) { /* -T */
+                       if (!(s_flags & 2) && (d_flags & 2))
+                               /* cp -T NOTDIR DIR */
+                               bb_error_msg_and_die("'%s' is a directory", last);
+               }
 
-    if ( (i->stat.st_mode & S_IFMT) == S_IFDIR ) {
-        if ( mkdir(destination, i->stat.st_mode & ~S_IFMT)
-         != 0 && errno != EEXIST ) {
-            name_and_error(destination);
-            return 1;
-        }
-        return 0;
-    }
-    if ( (sourceFd = open(i->source, O_RDONLY)) < 0 ) {
-        name_and_error(i->source);
-        return 1;
-    }
-    if ( stat(destination, &destination_stat) == 0 ) {
-        if ( i->stat.st_ino == destination_stat.st_ino
-         &&  i->stat.st_dev == destination_stat.st_dev ) {
-            fprintf(stderr
-            ,"copy of %s to %s would copy file to itself.\n"
-            ,i->source
-            ,destination);
-            close(sourceFd);
-            return 1;
-        }
-    }
-    /*
-     * If the destination is a directory, create a file within it.
-     */
-    if ( (destination_stat.st_mode & S_IFMT) == S_IFDIR ) {
-               destination = join_paths(
-                d
-               ,i->destination
-               ,&i->source[i->directoryLength]);
+#if ENABLE_FEATURE_CP_LONG_OPTIONS
+               //bb_error_msg("flags:%x FILEUTILS_RMDEST:%x OPT_parents:%x",
+               //      flags, FILEUTILS_RMDEST, OPT_parents);
+               if (flags & OPT_parents) {
+                       if (!(d_flags & 2)) {
+                               bb_error_msg_and_die("with --parents, the destination must be a directory");
+                       }
+               }
+               if (flags & FILEUTILS_RMDEST) {
+                       flags |= FILEUTILS_FORCE;
+               }
+#endif
 
-        if ( stat(destination, &destination_stat) == 0 ) {
-            if ( i->stat.st_ino == destination_stat.st_ino
-             &&  i->stat.st_dev == destination_stat.st_dev ) {
-                fprintf(stderr
-                ,"copy of %s to %s would copy file to itself.\n"
-                ,i->source
-                ,destination);
-                close(sourceFd);
-                return 1;
-            }
-        }
-    }
+               /* ...if neither is a directory...  */
+               if (!((s_flags | d_flags) & 2)
+                   /* ...or: recursing, the 1st is a directory, and the 2nd doesn't exist... */
+                || ((flags & FILEUTILS_RECUR) && (s_flags & 2) && !d_flags)
+                || (flags & FILEUTILS_NO_TARGET_DIR)
+               ) {
+                       /* Do a simple copy */
+                       dest = last;
+                       goto DO_COPY; /* NB: argc==2 -> *++argv==last */
+               }
+       } else if (flags & FILEUTILS_NO_TARGET_DIR) {
+               bb_error_msg_and_die("too many arguments");
+       }
 
-    destinationFd = creat(destination, i->stat.st_mode & 07777);
+       while (1) {
+#if ENABLE_FEATURE_CP_LONG_OPTIONS
+               if (flags & OPT_parents) {
+                       char *dest_dup;
+                       char *dest_dir;
+                       dest = concat_path_file(last, *argv);
+                       dest_dup = xstrdup(dest);
+                       dest_dir = dirname(dest_dup);
+                       if (bb_make_directory(dest_dir, -1, FILEUTILS_RECUR)) {
+                               return EXIT_FAILURE;
+                       }
+                       free(dest_dup);
+                       goto DO_COPY;
+               }
+#endif
+               dest = concat_path_file(last, bb_get_last_path_component_strip(*argv));
+ DO_COPY:
+               if (copy_file(*argv, dest, flags) < 0) {
+                       status = EXIT_FAILURE;
+               }
+               if (*++argv == last) {
+                       /* possibly leaking dest... */
+                       break;
+               }
+               /* don't move up: dest may be == last and not malloced! */
+               free((void*)dest);
+       }
 
-    while ( (status = read(sourceFd, buf, sizeof(buf))) > 0 ) {
-        if ( write(destinationFd, buf, status) != status ) {
-            name_and_error(destination);
-            close(sourceFd);
-            close(destinationFd);
-            return 1;
-        }
-    }
-    close(sourceFd);
-    close(destinationFd);
-    if ( status < 0 ) {
-        name_and_error(i->source);
-        return 1;
-    }
-    return 0;
+       /* Exit. We are NOEXEC, not NOFORK. We do exit at the end of main() */
+       return status;
 }