test prerequisites: enumerate with commas
[gitweb.git] / builtin / replace.c
index af40129c8fc30dd8e4c89d56187244e782620cc2..d1ea2c2e5606f2091efb487dc1599ec0a9116a6e 100644 (file)
 #include "builtin.h"
 #include "refs.h"
 #include "parse-options.h"
+#include "run-command.h"
 
 static const char * const git_replace_usage[] = {
        N_("git replace [-f] <object> <replacement>"),
+       N_("git replace [-f] --edit <object>"),
        N_("git replace -d <object>..."),
        N_("git replace [--format=<format>] [-l [<pattern>]]"),
        NULL
 };
 
 enum replace_format {
-      REPLACE_FORMAT_SHORT,
-      REPLACE_FORMAT_MEDIUM,
-      REPLACE_FORMAT_LONG
+       REPLACE_FORMAT_SHORT,
+       REPLACE_FORMAT_MEDIUM,
+       REPLACE_FORMAT_LONG
 };
 
 struct show_data {
@@ -123,6 +125,25 @@ static int delete_replace_ref(const char *name, const char *ref,
        return 0;
 }
 
+static void check_ref_valid(unsigned char object[20],
+                           unsigned char prev[20],
+                           char *ref,
+                           int ref_size,
+                           int force)
+{
+       if (snprintf(ref, ref_size,
+                    "refs/replace/%s",
+                    sha1_to_hex(object)) > ref_size - 1)
+               die("replace ref name too long: %.*s...", 50, ref);
+       if (check_refname_format(ref, 0))
+               die("'%s' is not a valid ref name.", ref);
+
+       if (read_ref(ref, prev))
+               hashclr(prev);
+       else if (!force)
+               die("replace ref '%s' already exists", ref);
+}
+
 static int replace_object_sha1(const char *object_ref,
                               unsigned char object[20],
                               const char *replace_ref,
@@ -134,13 +155,6 @@ static int replace_object_sha1(const char *object_ref,
        char ref[PATH_MAX];
        struct ref_lock *lock;
 
-       if (snprintf(ref, sizeof(ref),
-                    "refs/replace/%s",
-                    sha1_to_hex(object)) > sizeof(ref) - 1)
-               die("replace ref name too long: %.*s...", 50, ref);
-       if (check_refname_format(ref, 0))
-               die("'%s' is not a valid ref name.", ref);
-
        obj_type = sha1_object_info(object, NULL);
        repl_type = sha1_object_info(repl, NULL);
        if (!force && obj_type != repl_type)
@@ -150,10 +164,7 @@ static int replace_object_sha1(const char *object_ref,
                    object_ref, typename(obj_type),
                    replace_ref, typename(repl_type));
 
-       if (read_ref(ref, prev))
-               hashclr(prev);
-       else if (!force)
-               die("replace ref '%s' already exists", ref);
+       check_ref_valid(object, prev, ref, sizeof(ref), force);
 
        lock = lock_any_ref_for_update(ref, prev, 0, NULL);
        if (!lock)
@@ -176,20 +187,136 @@ static int replace_object(const char *object_ref, const char *replace_ref, int f
        return replace_object_sha1(object_ref, object, replace_ref, repl, force);
 }
 
+/*
+ * Write the contents of the object named by "sha1" to the file "filename".
+ * If "raw" is true, then the object's raw contents are printed according to
+ * "type". Otherwise, we pretty-print the contents for human editing.
+ */
+static void export_object(const unsigned char *sha1, enum object_type type,
+                         int raw, const char *filename)
+{
+       struct child_process cmd = { NULL };
+       int fd;
+
+       fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
+       if (fd < 0)
+               die_errno("unable to open %s for writing", filename);
+
+       argv_array_push(&cmd.args, "--no-replace-objects");
+       argv_array_push(&cmd.args, "cat-file");
+       if (raw)
+               argv_array_push(&cmd.args, typename(type));
+       else
+               argv_array_push(&cmd.args, "-p");
+       argv_array_push(&cmd.args, sha1_to_hex(sha1));
+       cmd.git_cmd = 1;
+       cmd.out = fd;
+
+       if (run_command(&cmd))
+               die("cat-file reported failure");
+}
+
+/*
+ * Read a previously-exported (and possibly edited) object back from "filename",
+ * interpreting it as "type", and writing the result to the object database.
+ * The sha1 of the written object is returned via sha1.
+ */
+static void import_object(unsigned char *sha1, enum object_type type,
+                         int raw, const char *filename)
+{
+       int fd;
+
+       fd = open(filename, O_RDONLY);
+       if (fd < 0)
+               die_errno("unable to open %s for reading", filename);
+
+       if (!raw && type == OBJ_TREE) {
+               const char *argv[] = { "mktree", NULL };
+               struct child_process cmd = { argv };
+               struct strbuf result = STRBUF_INIT;
+
+               cmd.argv = argv;
+               cmd.git_cmd = 1;
+               cmd.in = fd;
+               cmd.out = -1;
+
+               if (start_command(&cmd))
+                       die("unable to spawn mktree");
+
+               if (strbuf_read(&result, cmd.out, 41) < 0)
+                       die_errno("unable to read from mktree");
+               close(cmd.out);
+
+               if (finish_command(&cmd))
+                       die("mktree reported failure");
+               if (get_sha1_hex(result.buf, sha1) < 0)
+                       die("mktree did not return an object name");
+
+               strbuf_release(&result);
+       } else {
+               struct stat st;
+               int flags = HASH_FORMAT_CHECK | HASH_WRITE_OBJECT;
+
+               if (fstat(fd, &st) < 0)
+                       die_errno("unable to fstat %s", filename);
+               if (index_fd(sha1, fd, &st, type, NULL, flags) < 0)
+                       die("unable to write object to database");
+               /* index_fd close()s fd for us */
+       }
+
+       /*
+        * No need to close(fd) here; both run-command and index-fd
+        * will have done it for us.
+        */
+}
+
+static int edit_and_replace(const char *object_ref, int force, int raw)
+{
+       char *tmpfile = git_pathdup("REPLACE_EDITOBJ");
+       enum object_type type;
+       unsigned char old[20], new[20], prev[20];
+       char ref[PATH_MAX];
+
+       if (get_sha1(object_ref, old) < 0)
+               die("Not a valid object name: '%s'", object_ref);
+
+       type = sha1_object_info(old, NULL);
+       if (type < 0)
+               die("unable to get object type for %s", sha1_to_hex(old));
+
+       check_ref_valid(old, prev, ref, sizeof(ref), force);
+
+       export_object(old, type, raw, tmpfile);
+       if (launch_editor(tmpfile, NULL, NULL) < 0)
+               die("editing object file failed");
+       import_object(new, type, raw, tmpfile);
+
+       free(tmpfile);
+
+       if (!hashcmp(old, new))
+               return error("new object is the same as the old one: '%s'", sha1_to_hex(old));
+
+       return replace_object_sha1(object_ref, old, "replacement", new, force);
+}
+
 int cmd_replace(int argc, const char **argv, const char *prefix)
 {
        int force = 0;
+       int raw = 0;
        const char *format = NULL;
        enum {
                MODE_UNSPECIFIED = 0,
                MODE_LIST,
                MODE_DELETE,
+               MODE_EDIT,
                MODE_REPLACE
        } cmdmode = MODE_UNSPECIFIED;
        struct option options[] = {
                OPT_CMDMODE('l', "list", &cmdmode, N_("list replace refs"), MODE_LIST),
                OPT_CMDMODE('d', "delete", &cmdmode, N_("delete replace refs"), MODE_DELETE),
+               OPT_CMDMODE('e', "edit", &cmdmode, N_("edit existing object"), MODE_EDIT),
                OPT_BOOL('f', "force", &force, N_("replace the ref if it exists")),
+               OPT_BOOL(0, "raw", &raw, N_("do not pretty-print contents for --edit")),
                OPT_STRING(0, "format", &format, N_("format"), N_("use this format")),
                OPT_END()
        };
@@ -205,10 +332,14 @@ int cmd_replace(int argc, const char **argv, const char *prefix)
                usage_msg_opt("--format cannot be used when not listing",
                              git_replace_usage, options);
 
-       if (force && cmdmode != MODE_REPLACE)
+       if (force && cmdmode != MODE_REPLACE && cmdmode != MODE_EDIT)
                usage_msg_opt("-f only makes sense when writing a replacement",
                              git_replace_usage, options);
 
+       if (raw && cmdmode != MODE_EDIT)
+               usage_msg_opt("--raw only makes sense with --edit",
+                             git_replace_usage, options);
+
        switch (cmdmode) {
        case MODE_DELETE:
                if (argc < 1)
@@ -222,6 +353,12 @@ int cmd_replace(int argc, const char **argv, const char *prefix)
                                      git_replace_usage, options);
                return replace_object(argv[0], argv[1], force);
 
+       case MODE_EDIT:
+               if (argc != 1)
+                       usage_msg_opt("-e needs exactly one argument",
+                                     git_replace_usage, options);
+               return edit_and_replace(argv[0], force, raw);
+
        case MODE_LIST:
                if (argc > 1)
                        usage_msg_opt("only one pattern can be given with -l",