patch: support "patch [FILE [PATCH]]" format

function                                             old     new   delta
xopen_stdin                                            -      15     +15
patch_main                                          2075    2041     -34

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

4 files changed, 56 insertions, 12 deletions

diff --git a/editors/patch.c b/editors/patch.c
index 3ed4eba45..c40f54155 100644
--- a/editors/patch.c
+++ b/editors/patch.c
@@ -447,10 +447,21 @@ int patch_main(int argc UNUSED_PARAM, char **argv)
         INIT_TT();
 
         opts = getopt32(argv, FLAG_STR, &opt_p, &opt_i);
+        argv += optind;
         reverse = opts & FLAG_REVERSE;
         TT.prefix = (opts & FLAG_PATHLEN) ? xatoi(opt_p) : 0; // can be negative!
-        if (opts & FLAG_INPUT) TT.filepatch = xopen(opt_i, O_RDONLY);
         TT.filein = TT.fileout = -1;
+        if (opts & FLAG_INPUT) {
+                TT.filepatch = xopen_stdin(opt_i);
+        } else {
+                if (argv[0] && argv[1]) {
+                        TT.filepatch = xopen_stdin(argv[1]);
+                }
+        }
+        if (argv[0]) {
+                oldname = xstrdup(argv[0]);
+                newname = xstrdup(argv[0]);
+        }
 
         // Loop through the lines in the patch
         for(;;) {
@@ -498,18 +509,20 @@ int patch_main(int argc UNUSED_PARAM, char **argv)
                                 state = 1;
                         }
 
-                        free(*name);
                         finish_oldfile();
 
-                        // Trim date from end of filename (if any).  We don't care.
-                        for (s = patchline+4; *s && *s!='\t'; s++)
-                                if (*s=='\\' && s[1]) s++;
-                        i = atoi(s);
-                        if (i>1900 && i<=1970)
-                                *name = xstrdup("/dev/null");
-                        else {
-                                *s = 0;
-                                *name = xstrdup(patchline+4);
+                        if (!argv[0]) {
+                                free(*name);
+                                // Trim date from end of filename (if any).  We don't care.
+                                for (s = patchline+4; *s && *s!='\t'; s++)
+                                        if (*s=='\\' && s[1]) s++;
+                                i = atoi(s);
+                                if (i>1900 && i<=1970)
+                                        *name = xstrdup("/dev/null");
+                                else {
+                                        *s = 0;
+                                        *name = xstrdup(patchline+4);
+                                }
                         }
 
                         // We defer actually opening the file because svn produces broken
diff --git a/include/libbb.h b/include/libbb.h
index ac818a9ea..3fd754511 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -417,6 +417,7 @@ int xopen3(const char *pathname, int flags, int mode) FAST_FUNC;
 int open_or_warn(const char *pathname, int flags) FAST_FUNC;
 int open3_or_warn(const char *pathname, int flags, int mode) FAST_FUNC;
 int open_or_warn_stdin(const char *pathname) FAST_FUNC;
+int xopen_stdin(const char *pathname) FAST_FUNC;
 void xrename(const char *oldpath, const char *newpath) FAST_FUNC;
 int rename_or_warn(const char *oldpath, const char *newpath) FAST_FUNC;
 off_t xlseek(int fd, off_t offset, int whence) FAST_FUNC;
diff --git a/libbb/wfopen_input.c b/libbb/wfopen_input.c
index 7263c933a..422a58ecf 100644
--- a/libbb/wfopen_input.c
+++ b/libbb/wfopen_input.c
@@ -46,3 +46,11 @@ int FAST_FUNC open_or_warn_stdin(const char *filename)
 
         return fd;
 }
+
+int FAST_FUNC xopen_stdin(const char *filename)
+{
+        int fd = open_or_warn_stdin(filename);
+        if (fd >= 0)
+                return fd;
+        xfunc_die();    /* We already output an error message. */
+}
diff --git a/testsuite/patch.tests b/testsuite/patch.tests
index cd0e965cf..e482304f6 100755
--- a/testsuite/patch.tests
+++ b/testsuite/patch.tests
@@ -129,7 +129,6 @@ abc
 " \
 
 # testing "test name" "command(s)" "expected result" "file input" "stdin"
-
 testing "patch -N ignores already applied hunk" \
         'patch -N 2>&1; echo $?; cat input' \
 "\
@@ -153,6 +152,29 @@ def
  123
 " \
 
+# testing "test name" "command(s)" "expected result" "file input" "stdin"
+testing "patch FILE PATCH" \
+        'cat >a.patch; patch input a.patch 2>&1; echo $?; cat input; rm a.patch' \
+"\
+patching file input
+0
+abc
+def
+123
+" \
+"\
+abc
+123
+" \
+"\
+--- foo.old
++++ foo
+@@ -1,2 +1,3 @@
+ abc
++def
+ 123
+" \
+
 rm input.orig 2>/dev/null
 
 exit $FAILCOUNT