patch: busyboxify by migrating from toybox to busybox helpers

function                                             old     new   delta
get_line                                              90     128     +38
bbconfig_config_bz2                                 4959    4965      +6
makedevs_main                                       1038    1035      -3
fail_hunk                                            133     130      -3
finish_oldfile                                       174     124     -50
patch_main                                          2066    1987     -79
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/4 up/down: 44/-135)           Total: -91 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 87 insertions, 162 deletions

diff --git a/editors/patch.c b/editors/patch.c
index 33ff8b569..4fadbb8fe 100644
--- a/editors/patch.c
+++ b/editors/patch.c
@@ -1,8 +1,7 @@
-/* Adapted from toybox's patch. */
-
 /* vi: set sw=4 ts=4:
  *
- * patch.c - Apply a "universal" diff.
+ * Apply a "universal" diff.
+ * Adapted from toybox's patch implementation.
  *
  * Copyright 2007 Rob Landley <rob@landley.net>
  *
@@ -20,29 +19,41 @@
  * -f force (no questions asked)
  * -F fuzz (number, default 2)
  * [file] which file to patch
+ */
+
+//applet:IF_PATCH(APPLET(patch, _BB_DIR_USR_BIN, _BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_PATCH) += patch.o
+
+//config:config PATCH
+//config:       bool "patch"
+//config:       default y
+//config:       help
+//config:         Apply a unified diff formatted patch.
+
+//usage:#define patch_trivial_usage
+//usage:       "[OPTIONS] [ORIGFILE [PATCHFILE]]"
+//usage:#define patch_full_usage "\n\n"
+//usage:        IF_LONG_OPTS(
+//usage:       "        -p,--strip N            Strip N leading components from file names"
+//usage:     "\n        -i,--input DIFF         Read DIFF instead of stdin"
+//usage:     "\n        -R,--reverse            Reverse patch"
+//usage:     "\n        -N,--forward            Ignore already applied patches"
+//usage:     "\n        --dry-run               Don't actually change files"
+//usage:     "\n        -E,--remove-empty-files Remove output files if they become empty"
+//usage:        )
+//usage:        IF_NOT_LONG_OPTS(
+//usage:       "        -p N    Strip N leading components from file names"
+//usage:     "\n        -i DIFF Read DIFF instead of stdin"
+//usage:     "\n        -R      Reverse patch"
+//usage:     "\n        -N      Ignore already applied patches"
+//usage:     "\n        -E      Remove output files if they become empty"
+//usage:        )
+//usage:
+//usage:#define patch_example_usage
+//usage:       "$ patch -p1 < example.diff\n"
+//usage:       "$ patch -p0 -i example.diff"
 
-USE_PATCH(NEWTOY(patch, USE_TOYBOX_DEBUG("x")"up#i:R", TOYFLAG_USR|TOYFLAG_BIN))
-
-config PATCH
-        bool "patch"
-        default y
-        help
-          usage: patch [-i file] [-p depth] [-Ru]
-
-          Apply a unified diff to one or more files.
-
-          -i    Input file (defaults=stdin)
-          -p    number of '/' to strip from start of file paths (default=all)
-          -R    Reverse patch.
-          -u    Ignored (only handles "unified" diffs)
-
-          This version of patch only handles unified diffs, and only modifies
-          a file when all all hunks to that file apply.  Patch prints failed
-          hunks to stderr, and exits with nonzero status if any hunks fail.
-
-          A file compared against /dev/null (or with a date <= the epoch) is
-          created or deleted if -E or --remove-empty-files set.
-*/
 #include "libbb.h"
 
 struct double_list {
@@ -101,125 +112,6 @@ struct double_list *dlist_add(struct double_list **list, char *data)
         return line;
 }
 
-// Ensure entire path exists.
-// If mode != -1 set permissions on newly created dirs.
-// Requires that path string be writable (for temporary null terminators).
-static
-void xmkpath(char *path, int mode)
-{
-        char *p, old;
-        mode_t mask;
-        int rc;
-        struct stat st;
-
-        for (p = path; ; p++) {
-                if (!*p || *p == '/') {
-                        old = *p;
-                        *p = rc = 0;
-                        if (stat(path, &st) || !S_ISDIR(st.st_mode)) {
-                                if (mode != -1) {
-                                        mask = umask(0);
-                                        rc = mkdir(path, mode);
-                                        umask(mask);
-                                } else rc = mkdir(path, 0777);
-                        }
-                        *p = old;
-                        if(rc) bb_perror_msg_and_die("mkpath '%s'", path);
-                }
-                if (!*p) break;
-        }
-}
-
-// Slow, but small.
-static
-char *get_rawline(int fd, long *plen, char end)
-{
-        char c, *buf = NULL;
-        long len = 0;
-
-        for (;;) {
-                if (1>read(fd, &c, 1)) break;
-                if (!(len & 63)) buf=xrealloc(buf, len+65);
-                if ((buf[len++]=c) == end) break;
-        }
-        if (buf) buf[len]=0;
-        if (plen) *plen = len;
-
-        return buf;
-}
-
-static
-char *get_line(int fd)
-{
-        long len;
-        char *buf = get_rawline(fd, &len, '\n');
-
-        if (buf && buf[--len]=='\n') buf[len]=0;
-
-        return buf;
-}
-
-// Copy the rest of in to out and close both files.
-static
-void xsendfile(int in, int out)
-{
-        long len;
-        char buf[4096];
-
-        if (in<0) return;
-        for (;;) {
-                len = safe_read(in, buf, 4096);
-                if (len<1) break;
-                xwrite(out, buf, len);
-        }
-}
-
-// Copy the rest of the data and replace the original with the copy.
-static
-void replace_tempfile(int fdin, int fdout, char **tempname)
-{
-        char *temp = xstrdup(*tempname);
-
-        temp[strlen(temp)-6]=0;
-        if (fdin != -1) {
-                xsendfile(fdin, fdout);
-                xclose(fdin);
-        }
-        xclose(fdout);
-        rename(*tempname, temp);
-        free(*tempname);
-        free(temp);
-        *tempname = NULL;
-}
-
-// Open a temporary file to copy an existing file into.
-static
-int copy_tempfile(int fdin, char *name, char **tempname)
-{
-        struct stat statbuf;
-        int fd;
-
-        *tempname = xasprintf("%sXXXXXX", name);
-        fd = xmkstemp(*tempname);
-
-        // Set permissions of output file
-        fstat(fdin, &statbuf);
-        fchmod(fd, statbuf.st_mode);
-
-        return fd;
-}
-
-// Abort the copy and delete the temporary file.
-static
-void delete_tempfile(int fdin, int fdout, char **tempname)
-{
-        close(fdin);
-        close(fdout);
-        unlink(*tempname);
-        free(*tempname);
-        *tempname = NULL;
-}
-
 
 
 struct globals {
@@ -229,7 +121,7 @@ struct globals {
         struct double_list *current_hunk;
         long oldline, oldlen, newline, newlen;
         long linenum;
-        int context, state, filein, fileout, filepatch, hunknum;
+        int context, state, filein, fileout, hunknum;
         char *tempname;
 
         // was toys.foo:
@@ -263,7 +155,7 @@ struct globals {
 
 static void do_line(void *data)
 {
-        struct double_list *dlist = (struct double_list *)data;
+        struct double_list *dlist = data;
 
         if (TT.state>1 && *dlist->data != TT.state)
                 fdprintf(TT.state == 2 ? 2 : TT.fileout,
@@ -272,19 +164,36 @@ static void do_line(void *data)
         if (PATCH_DEBUG) fdprintf(2, "DO %d: %s\n", TT.state, dlist->data);
 
         free(dlist->data);
-        free(data);
+        free(dlist);
 }
 
 static void finish_oldfile(void)
 {
-        if (TT.tempname) replace_tempfile(TT.filein, TT.fileout, &TT.tempname);
+        if (TT.tempname) {
+                // Copy the rest of the data and replace the original with the copy.
+                char *temp;
+
+                if (TT.filein != -1) {
+                        bb_copyfd_eof(TT.filein, TT.fileout);
+                        xclose(TT.filein);
+                }
+                xclose(TT.fileout);
+
+                temp = xstrdup(TT.tempname);
+                temp[strlen(temp) - 6] = '\0';
+                rename(TT.tempname, temp);
+                free(temp);
+
+                free(TT.tempname);
+                TT.tempname = NULL;
+        }
         TT.fileout = TT.filein = -1;
 }
 
 static void fail_hunk(void)
 {
         if (!TT.current_hunk) return;
-        TT.current_hunk->prev->next = 0;
+        TT.current_hunk->prev->next = NULL;
 
         fdprintf(2, "Hunk %d FAILED %ld/%ld.\n", TT.hunknum, TT.oldline, TT.newline);
         TT.exitval = 1;
@@ -295,7 +204,14 @@ static void fail_hunk(void)
         TT.state = 2;
         llist_free(TT.current_hunk, do_line);
         TT.current_hunk = NULL;
-        delete_tempfile(TT.filein, TT.fileout, &TT.tempname);
+
+        // Abort the copy and delete the temporary file.
+        close(TT.filein);
+        close(TT.fileout);
+        unlink(TT.tempname);
+        free(TT.tempname);
+        TT.tempname = NULL;
+
         TT.state = 0;
 }
 
@@ -334,7 +250,7 @@ static int apply_one_hunk(void)
         plist = TT.current_hunk;
         buf = NULL;
         if (TT.context) for (;;) {
-                char *data = get_line(TT.filein);
+                char *data = xmalloc_reads(TT.filein, NULL, NULL);
 
                 TT.linenum++;
 
@@ -368,7 +284,9 @@ static int apply_one_hunk(void)
                         // File ended before we found a place for this hunk.
                         fail_hunk();
                         goto done;
-                } else if (PATCH_DEBUG) fdprintf(2, "IN: %s\n", data);
+                }
+
+                if (PATCH_DEBUG) fdprintf(2, "IN: %s\n", data);
                 check = dlist_add(&buf, data);
 
                 // Compare this line with next expected line of hunk.
@@ -398,8 +316,8 @@ static int apply_one_hunk(void)
 
                                 // If we've reached the end of the buffer without confirming a
                                 // match, read more lines.
-                                if (check==buf) {
-                                        buf = 0;
+                                if (check == buf) {
+                                        buf = NULL;
                                         break;
                                 }
                                 check = buf;
@@ -453,10 +371,10 @@ int patch_main(int argc UNUSED_PARAM, char **argv)
         TT.prefix = (opts & FLAG_PATHLEN) ? xatoi(opt_p) : 0; // can be negative!
         TT.filein = TT.fileout = -1;
         if (opts & FLAG_INPUT) {
-                TT.filepatch = xopen_stdin(opt_i);
+                xmove_fd(xopen_stdin(opt_i), STDIN_FILENO);
         } else {
                 if (argv[0] && argv[1]) {
-                        TT.filepatch = xopen_stdin(argv[1]);
+                        xmove_fd(xopen_stdin(argv[1]), STDIN_FILENO);
                 }
         }
         if (argv[0]) {
@@ -468,7 +386,7 @@ int patch_main(int argc UNUSED_PARAM, char **argv)
         for(;;) {
                 char *patchline;
 
-                patchline = get_line(TT.filepatch);
+                patchline = xmalloc_fgetline(stdin);
                 if (!patchline) break;
 
                 // Other versions of patch accept damaged patches,
@@ -588,13 +506,15 @@ int patch_main(int argc UNUSED_PARAM, char **argv)
                                         }
                                 // If we've got a file to open, do so.
                                 } else if (!(option_mask32 & FLAG_PATHLEN) || i <= TT.prefix) {
+                                        struct stat statbuf;
+
                                         // If the old file was null, we're creating a new one.
                                         if (!strcmp(oldname, "/dev/null") || !oldsum) {
                                                 printf("creating %s\n", name);
                                                 s = strrchr(name, '/');
                                                 if (s) {
                                                         *s = 0;
-                                                        xmkpath(name, -1);
+                                                        bb_make_directory(name, -1, FILEUTILS_RECUR);
                                                         *s = '/';
                                                 }
                                                 TT.filein = xopen(name, O_CREAT|O_EXCL|O_RDWR);
@@ -602,7 +522,13 @@ int patch_main(int argc UNUSED_PARAM, char **argv)
                                                 printf("patching file %s\n", name);
                                                 TT.filein = xopen(name, O_RDONLY);
                                         }
-                                        TT.fileout = copy_tempfile(TT.filein, name, &TT.tempname);
+
+                                        TT.tempname = xasprintf("%sXXXXXX", name);
+                                        TT.fileout = xmkstemp(TT.tempname);
+                                        // Set permissions of output file
+                                        fstat(TT.filein, &statbuf);
+                                        fchmod(TT.fileout, statbuf.st_mode);
+
                                         TT.linenum = 0;
                                         TT.hunknum = 0;
                                 }
@@ -620,7 +546,6 @@ int patch_main(int argc UNUSED_PARAM, char **argv)
         finish_oldfile();
 
         if (ENABLE_FEATURE_CLEAN_UP) {
-                close(TT.filepatch);
                 free(oldname);
                 free(newname);
         }
diff --git a/testsuite/patch.tests b/testsuite/patch.tests
index e482304f6..ba37e8218 100755
--- a/testsuite/patch.tests
+++ b/testsuite/patch.tests
@@ -75,7 +75,7 @@ zxc
 testing "patch detects already applied hunk" \
         'patch 2>&1; echo $?; cat input' \
 "\
-Possibly reversed hunk 1 at 2
+Possibly reversed hunk 1 at 4
 Hunk 1 FAILED 1/1.
  abc
 +def
@@ -103,7 +103,7 @@ def
 testing "patch detects already applied hunk at the EOF" \
         'patch 2>&1; echo $?; cat input' \
 "\
-Possibly reversed hunk 1 at 3
+Possibly reversed hunk 1 at 4
 Hunk 1 FAILED 1/1.
  abc
  123