]> asedeno.scripts.mit.edu Git - git.git/blobdiff - merge-recursive.c
Merge branch 'np/progress'
[git.git] / merge-recursive.c
index 31e66e5ca3811d6356a635ef7580e86ce9c83863..6c6f595fbc7da09a41228e09cd2c5ef48b91f3f0 100644 (file)
@@ -15,6 +15,8 @@
 #include "unpack-trees.h"
 #include "path-list.h"
 #include "xdiff-interface.h"
+#include "interpolate.h"
+#include "attr.h"
 
 static int subtree_merge;
 
@@ -83,63 +85,59 @@ struct stage_data
        unsigned processed:1;
 };
 
-struct output_buffer
-{
-       struct output_buffer *next;
-       char *str;
-};
-
 static struct path_list current_file_set = {NULL, 0, 0, 1};
 static struct path_list current_directory_set = {NULL, 0, 0, 1};
 
 static int call_depth = 0;
 static int verbosity = 2;
+static int rename_limit = -1;
 static int buffer_output = 1;
-static struct output_buffer *output_list, *output_end;
+static struct strbuf obuf = STRBUF_INIT;
 
-static int show (int v)
+static int show(int v)
 {
        return (!call_depth && verbosity >= v) || verbosity >= 5;
 }
 
-static void output(int v, const char *fmt, ...)
+static void flush_output(void)
 {
-       va_list args;
-       va_start(args, fmt);
-       if (buffer_output && show(v)) {
-               struct output_buffer *b = xmalloc(sizeof(*b));
-               nfvasprintf(&b->str, fmt, args);
-               b->next = NULL;
-               if (output_end)
-                       output_end->next = b;
-               else
-                       output_list = b;
-               output_end = b;
-       } else if (show(v)) {
-               int i;
-               for (i = call_depth; i--;)
-                       fputs("  ", stdout);
-               vfprintf(stdout, fmt, args);
-               fputc('\n', stdout);
+       if (obuf.len) {
+               fputs(obuf.buf, stdout);
+               strbuf_reset(&obuf);
        }
-       va_end(args);
 }
 
-static void flush_output()
+static void output(int v, const char *fmt, ...)
 {
-       struct output_buffer *b, *n;
-       for (b = output_list; b; b = n) {
-               int i;
-               for (i = call_depth; i--;)
-                       fputs("  ", stdout);
-               fputs(b->str, stdout);
-               fputc('\n', stdout);
-               n = b->next;
-               free(b->str);
-               free(b);
+       int len;
+       va_list ap;
+
+       if (!show(v))
+               return;
+
+       strbuf_grow(&obuf, call_depth * 2 + 2);
+       memset(obuf.buf + obuf.len, ' ', call_depth * 2);
+       strbuf_setlen(&obuf, obuf.len + call_depth * 2);
+
+       va_start(ap, fmt);
+       len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
+       va_end(ap);
+
+       if (len < 0)
+               len = 0;
+       if (len >= strbuf_avail(&obuf)) {
+               strbuf_grow(&obuf, len + 2);
+               va_start(ap, fmt);
+               len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
+               va_end(ap);
+               if (len >= strbuf_avail(&obuf)) {
+                       die("this should not happen, your snprintf is broken");
+               }
        }
-       output_list = NULL;
-       output_end = NULL;
+       strbuf_setlen(&obuf, obuf.len + len);
+       strbuf_add(&obuf, "\n", 1);
+       if (!buffer_output)
+               flush_output();
 }
 
 static void output_commit_title(struct commit *commit)
@@ -169,30 +167,6 @@ static void output_commit_title(struct commit *commit)
        }
 }
 
-static struct cache_entry *make_cache_entry(unsigned int mode,
-               const unsigned char *sha1, const char *path, int stage, int refresh)
-{
-       int size, len;
-       struct cache_entry *ce;
-
-       if (!verify_path(path))
-               return NULL;
-
-       len = strlen(path);
-       size = cache_entry_size(len);
-       ce = xcalloc(1, size);
-
-       hashcpy(ce->sha1, sha1);
-       memcpy(ce->name, path, len);
-       ce->ce_flags = create_ce_flags(len, stage);
-       ce->ce_mode = create_ce_mode(mode);
-
-       if (refresh)
-               return refresh_cache_entry(ce, 0);
-
-       return ce;
-}
-
 static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
                const char *path, int stage, int refresh, int options)
 {
@@ -214,13 +188,19 @@ static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
  */
 static int index_only = 0;
 
+static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
+{
+       parse_tree(tree);
+       init_tree_desc(desc, tree->buffer, tree->size);
+}
+
 static int git_merge_trees(int index_only,
                           struct tree *common,
                           struct tree *head,
                           struct tree *merge)
 {
        int rc;
-       struct object_list *trees = NULL;
+       struct tree_desc t[3];
        struct unpack_trees_options opts;
 
        memset(&opts, 0, sizeof(opts));
@@ -232,11 +212,11 @@ static int git_merge_trees(int index_only,
        opts.head_idx = 2;
        opts.fn = threeway_merge;
 
-       object_list_append(&common->object, &trees);
-       object_list_append(&head->object, &trees);
-       object_list_append(&merge->object, &trees);
+       init_tree_desc_from_tree(t+0, common);
+       init_tree_desc_from_tree(t+1, head);
+       init_tree_desc_from_tree(t+2, merge);
 
-       rc = unpack_trees(trees, &opts);
+       rc = unpack_trees(3, t, &opts);
        cache_tree_free(&active_cache_tree);
        return rc;
 }
@@ -388,6 +368,7 @@ static struct path_list *get_renames(struct tree *tree,
        diff_setup(&opts);
        opts.recursive = 1;
        opts.detect_rename = DIFF_DETECT_RENAME;
+       opts.rename_limit = rename_limit;
        opts.output_format = DIFF_FORMAT_NO_OUTPUT;
        if (diff_setup_done(&opts) < 0)
                die("diff setup failed");
@@ -448,19 +429,15 @@ static int update_stages(const char *path, struct diff_filespec *o,
 
 static int remove_path(const char *name)
 {
-       int ret, len;
+       int ret;
        char *slash, *dirs;
 
        ret = unlink(name);
        if (ret)
                return ret;
-       len = strlen(name);
-       dirs = xmalloc(len+1);
-       memcpy(dirs, name, len);
-       dirs[len] = '\0';
+       dirs = xstrdup(name);
        while ((slash = strrchr(name, '/'))) {
                *slash = '\0';
-               len = slash - name;
                if (rmdir(name) != 0)
                        break;
        }
@@ -594,9 +571,7 @@ static void update_file_flags(const unsigned char *sha,
                        flush_buffer(fd, buf, size);
                        close(fd);
                } else if (S_ISLNK(mode)) {
-                       char *lnk = xmalloc(size + 1);
-                       memcpy(lnk, buf, size);
-                       lnk[size] = '\0';
+                       char *lnk = xmemdupz(buf, size);
                        mkdir_p(path, 0777);
                        unlink(path);
                        symlink(lnk, path);
@@ -645,6 +620,388 @@ static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
        mm->size = size;
 }
 
+/*
+ * Customizable low-level merge drivers support.
+ */
+
+struct ll_merge_driver;
+typedef int (*ll_merge_fn)(const struct ll_merge_driver *,
+                          const char *path,
+                          mmfile_t *orig,
+                          mmfile_t *src1, const char *name1,
+                          mmfile_t *src2, const char *name2,
+                          mmbuffer_t *result);
+
+struct ll_merge_driver {
+       const char *name;
+       const char *description;
+       ll_merge_fn fn;
+       const char *recursive;
+       struct ll_merge_driver *next;
+       char *cmdline;
+};
+
+/*
+ * Built-in low-levels
+ */
+static int ll_binary_merge(const struct ll_merge_driver *drv_unused,
+                          const char *path_unused,
+                          mmfile_t *orig,
+                          mmfile_t *src1, const char *name1,
+                          mmfile_t *src2, const char *name2,
+                          mmbuffer_t *result)
+{
+       /*
+        * The tentative merge result is "ours" for the final round,
+        * or common ancestor for an internal merge.  Still return
+        * "conflicted merge" status.
+        */
+       mmfile_t *stolen = index_only ? orig : src1;
+
+       result->ptr = stolen->ptr;
+       result->size = stolen->size;
+       stolen->ptr = NULL;
+       return 1;
+}
+
+static int ll_xdl_merge(const struct ll_merge_driver *drv_unused,
+                       const char *path_unused,
+                       mmfile_t *orig,
+                       mmfile_t *src1, const char *name1,
+                       mmfile_t *src2, const char *name2,
+                       mmbuffer_t *result)
+{
+       xpparam_t xpp;
+
+       if (buffer_is_binary(orig->ptr, orig->size) ||
+           buffer_is_binary(src1->ptr, src1->size) ||
+           buffer_is_binary(src2->ptr, src2->size)) {
+               warning("Cannot merge binary files: %s vs. %s\n",
+                       name1, name2);
+               return ll_binary_merge(drv_unused, path_unused,
+                                      orig, src1, name1,
+                                      src2, name2,
+                                      result);
+       }
+
+       memset(&xpp, 0, sizeof(xpp));
+       return xdl_merge(orig,
+                        src1, name1,
+                        src2, name2,
+                        &xpp, XDL_MERGE_ZEALOUS,
+                        result);
+}
+
+static int ll_union_merge(const struct ll_merge_driver *drv_unused,
+                         const char *path_unused,
+                         mmfile_t *orig,
+                         mmfile_t *src1, const char *name1,
+                         mmfile_t *src2, const char *name2,
+                         mmbuffer_t *result)
+{
+       char *src, *dst;
+       long size;
+       const int marker_size = 7;
+
+       int status = ll_xdl_merge(drv_unused, path_unused,
+                                 orig, src1, NULL, src2, NULL, result);
+       if (status <= 0)
+               return status;
+       size = result->size;
+       src = dst = result->ptr;
+       while (size) {
+               char ch;
+               if ((marker_size < size) &&
+                   (*src == '<' || *src == '=' || *src == '>')) {
+                       int i;
+                       ch = *src;
+                       for (i = 0; i < marker_size; i++)
+                               if (src[i] != ch)
+                                       goto not_a_marker;
+                       if (src[marker_size] != '\n')
+                               goto not_a_marker;
+                       src += marker_size + 1;
+                       size -= marker_size + 1;
+                       continue;
+               }
+       not_a_marker:
+               do {
+                       ch = *src++;
+                       *dst++ = ch;
+                       size--;
+               } while (ch != '\n' && size);
+       }
+       result->size = dst - result->ptr;
+       return 0;
+}
+
+#define LL_BINARY_MERGE 0
+#define LL_TEXT_MERGE 1
+#define LL_UNION_MERGE 2
+static struct ll_merge_driver ll_merge_drv[] = {
+       { "binary", "built-in binary merge", ll_binary_merge },
+       { "text", "built-in 3-way text merge", ll_xdl_merge },
+       { "union", "built-in union merge", ll_union_merge },
+};
+
+static void create_temp(mmfile_t *src, char *path)
+{
+       int fd;
+
+       strcpy(path, ".merge_file_XXXXXX");
+       fd = xmkstemp(path);
+       if (write_in_full(fd, src->ptr, src->size) != src->size)
+               die("unable to write temp-file");
+       close(fd);
+}
+
+/*
+ * User defined low-level merge driver support.
+ */
+static int ll_ext_merge(const struct ll_merge_driver *fn,
+                       const char *path,
+                       mmfile_t *orig,
+                       mmfile_t *src1, const char *name1,
+                       mmfile_t *src2, const char *name2,
+                       mmbuffer_t *result)
+{
+       char temp[3][50];
+       char cmdbuf[2048];
+       struct interp table[] = {
+               { "%O" },
+               { "%A" },
+               { "%B" },
+       };
+       struct child_process child;
+       const char *args[20];
+       int status, fd, i;
+       struct stat st;
+
+       if (fn->cmdline == NULL)
+               die("custom merge driver %s lacks command line.", fn->name);
+
+       result->ptr = NULL;
+       result->size = 0;
+       create_temp(orig, temp[0]);
+       create_temp(src1, temp[1]);
+       create_temp(src2, temp[2]);
+
+       interp_set_entry(table, 0, temp[0]);
+       interp_set_entry(table, 1, temp[1]);
+       interp_set_entry(table, 2, temp[2]);
+
+       output(1, "merging %s using %s", path,
+              fn->description ? fn->description : fn->name);
+
+       interpolate(cmdbuf, sizeof(cmdbuf), fn->cmdline, table, 3);
+
+       memset(&child, 0, sizeof(child));
+       child.argv = args;
+       args[0] = "sh";
+       args[1] = "-c";
+       args[2] = cmdbuf;
+       args[3] = NULL;
+
+       status = run_command(&child);
+       if (status < -ERR_RUN_COMMAND_FORK)
+               ; /* failure in run-command */
+       else
+               status = -status;
+       fd = open(temp[1], O_RDONLY);
+       if (fd < 0)
+               goto bad;
+       if (fstat(fd, &st))
+               goto close_bad;
+       result->size = st.st_size;
+       result->ptr = xmalloc(result->size + 1);
+       if (read_in_full(fd, result->ptr, result->size) != result->size) {
+               free(result->ptr);
+               result->ptr = NULL;
+               result->size = 0;
+       }
+ close_bad:
+       close(fd);
+ bad:
+       for (i = 0; i < 3; i++)
+               unlink(temp[i]);
+       return status;
+}
+
+/*
+ * merge.default and merge.driver configuration items
+ */
+static struct ll_merge_driver *ll_user_merge, **ll_user_merge_tail;
+static const char *default_ll_merge;
+
+static int read_merge_config(const char *var, const char *value)
+{
+       struct ll_merge_driver *fn;
+       const char *ep, *name;
+       int namelen;
+
+       if (!strcmp(var, "merge.default")) {
+               if (value)
+                       default_ll_merge = strdup(value);
+               return 0;
+       }
+
+       /*
+        * We are not interested in anything but "merge.<name>.variable";
+        * especially, we do not want to look at variables such as
+        * "merge.summary", "merge.tool", and "merge.verbosity".
+        */
+       if (prefixcmp(var, "merge.") || (ep = strrchr(var, '.')) == var + 5)
+               return 0;
+
+       /*
+        * Find existing one as we might be processing merge.<name>.var2
+        * after seeing merge.<name>.var1.
+        */
+       name = var + 6;
+       namelen = ep - name;
+       for (fn = ll_user_merge; fn; fn = fn->next)
+               if (!strncmp(fn->name, name, namelen) && !fn->name[namelen])
+                       break;
+       if (!fn) {
+               fn = xcalloc(1, sizeof(struct ll_merge_driver));
+               fn->name = xmemdupz(name, namelen);
+               fn->fn = ll_ext_merge;
+               *ll_user_merge_tail = fn;
+               ll_user_merge_tail = &(fn->next);
+       }
+
+       ep++;
+
+       if (!strcmp("name", ep)) {
+               if (!value)
+                       return error("%s: lacks value", var);
+               fn->description = strdup(value);
+               return 0;
+       }
+
+       if (!strcmp("driver", ep)) {
+               if (!value)
+                       return error("%s: lacks value", var);
+               /*
+                * merge.<name>.driver specifies the command line:
+                *
+                *      command-line
+                *
+                * The command-line will be interpolated with the following
+                * tokens and is given to the shell:
+                *
+                *    %O - temporary file name for the merge base.
+                *    %A - temporary file name for our version.
+                *    %B - temporary file name for the other branches' version.
+                *
+                * The external merge driver should write the results in the
+                * file named by %A, and signal that it has done with zero exit
+                * status.
+                */
+               fn->cmdline = strdup(value);
+               return 0;
+       }
+
+       if (!strcmp("recursive", ep)) {
+               if (!value)
+                       return error("%s: lacks value", var);
+               fn->recursive = strdup(value);
+               return 0;
+       }
+
+       return 0;
+}
+
+static void initialize_ll_merge(void)
+{
+       if (ll_user_merge_tail)
+               return;
+       ll_user_merge_tail = &ll_user_merge;
+       git_config(read_merge_config);
+}
+
+static const struct ll_merge_driver *find_ll_merge_driver(const char *merge_attr)
+{
+       struct ll_merge_driver *fn;
+       const char *name;
+       int i;
+
+       initialize_ll_merge();
+
+       if (ATTR_TRUE(merge_attr))
+               return &ll_merge_drv[LL_TEXT_MERGE];
+       else if (ATTR_FALSE(merge_attr))
+               return &ll_merge_drv[LL_BINARY_MERGE];
+       else if (ATTR_UNSET(merge_attr)) {
+               if (!default_ll_merge)
+                       return &ll_merge_drv[LL_TEXT_MERGE];
+               else
+                       name = default_ll_merge;
+       }
+       else
+               name = merge_attr;
+
+       for (fn = ll_user_merge; fn; fn = fn->next)
+               if (!strcmp(fn->name, name))
+                       return fn;
+
+       for (i = 0; i < ARRAY_SIZE(ll_merge_drv); i++)
+               if (!strcmp(ll_merge_drv[i].name, name))
+                       return &ll_merge_drv[i];
+
+       /* default to the 3-way */
+       return &ll_merge_drv[LL_TEXT_MERGE];
+}
+
+static const char *git_path_check_merge(const char *path)
+{
+       static struct git_attr_check attr_merge_check;
+
+       if (!attr_merge_check.attr)
+               attr_merge_check.attr = git_attr("merge", 5);
+
+       if (git_checkattr(path, 1, &attr_merge_check))
+               return NULL;
+       return attr_merge_check.value;
+}
+
+static int ll_merge(mmbuffer_t *result_buf,
+                   struct diff_filespec *o,
+                   struct diff_filespec *a,
+                   struct diff_filespec *b,
+                   const char *branch1,
+                   const char *branch2)
+{
+       mmfile_t orig, src1, src2;
+       char *name1, *name2;
+       int merge_status;
+       const char *ll_driver_name;
+       const struct ll_merge_driver *driver;
+
+       name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
+       name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
+
+       fill_mm(o->sha1, &orig);
+       fill_mm(a->sha1, &src1);
+       fill_mm(b->sha1, &src2);
+
+       ll_driver_name = git_path_check_merge(a->path);
+       driver = find_ll_merge_driver(ll_driver_name);
+
+       if (index_only && driver->recursive)
+               driver = find_ll_merge_driver(driver->recursive);
+       merge_status = driver->fn(driver, a->path,
+                                 &orig, &src1, name1, &src2, name2,
+                                 result_buf);
+
+       free(name1);
+       free(name2);
+       free(orig.ptr);
+       free(src1.ptr);
+       free(src2.ptr);
+       return merge_status;
+}
+
 static struct merge_file_info merge_file(struct diff_filespec *o,
                struct diff_filespec *a, struct diff_filespec *b,
                const char *branch1, const char *branch2)
@@ -673,30 +1030,11 @@ static struct merge_file_info merge_file(struct diff_filespec *o,
                else if (sha_eq(b->sha1, o->sha1))
                        hashcpy(result.sha, a->sha1);
                else if (S_ISREG(a->mode)) {
-                       mmfile_t orig, src1, src2;
                        mmbuffer_t result_buf;
-                       xpparam_t xpp;
-                       char *name1, *name2;
                        int merge_status;
 
-                       name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
-                       name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
-
-                       fill_mm(o->sha1, &orig);
-                       fill_mm(a->sha1, &src1);
-                       fill_mm(b->sha1, &src2);
-
-                       memset(&xpp, 0, sizeof(xpp));
-                       merge_status = xdl_merge(&orig,
-                                                &src1, name1,
-                                                &src2, name2,
-                                                &xpp, XDL_MERGE_ZEALOUS,
-                                                &result_buf);
-                       free(name1);
-                       free(name2);
-                       free(orig.ptr);
-                       free(src1.ptr);
-                       free(src2.ptr);
+                       merge_status = ll_merge(&result_buf, o, a, b,
+                                               branch1, branch2);
 
                        if ((merge_status < 0) || !result_buf.ptr)
                                die("Failed to execute internal merge");
@@ -981,20 +1319,31 @@ static int process_renames(struct path_list *a_renames,
                                mfi = merge_file(o, a, b,
                                                a_branch, b_branch);
 
-                               if (mfi.merge || !mfi.clean)
-                                       output(1, "Renamed %s => %s", ren1_src, ren1_dst);
-                               if (mfi.merge)
-                                       output(2, "Auto-merged %s", ren1_dst);
-                               if (!mfi.clean) {
-                                       output(1, "CONFLICT (rename/modify): Merge conflict in %s",
-                                              ren1_dst);
-                                       clean_merge = 0;
-
-                                       if (!index_only)
-                                               update_stages(ren1_dst,
-                                                               o, a, b, 1);
+                               if (mfi.clean &&
+                                   sha_eq(mfi.sha, ren1->pair->two->sha1) &&
+                                   mfi.mode == ren1->pair->two->mode)
+                                       /*
+                                        * This messaged is part of
+                                        * t6022 test. If you change
+                                        * it update the test too.
+                                        */
+                                       output(3, "Skipped %s (merged same as existing)", ren1_dst);
+                               else {
+                                       if (mfi.merge || !mfi.clean)
+                                               output(1, "Renamed %s => %s", ren1_src, ren1_dst);
+                                       if (mfi.merge)
+                                               output(2, "Auto-merged %s", ren1_dst);
+                                       if (!mfi.clean) {
+                                               output(1, "CONFLICT (rename/modify): Merge conflict in %s",
+                                                      ren1_dst);
+                                               clean_merge = 0;
+
+                                               if (!index_only)
+                                                       update_stages(ren1_dst,
+                                                                     o, a, b, 1);
+                                       }
+                                       update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
                                }
-                               update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
                        }
                }
        }
@@ -1223,7 +1572,7 @@ static int merge(struct commit *h1,
 {
        struct commit_list *iter;
        struct commit *merged_common_ancestors;
-       struct tree *mrtree;
+       struct tree *mrtree = mrtree;
        int clean;
 
        if (show(4)) {
@@ -1330,6 +1679,10 @@ static int merge_config(const char *var, const char *value)
                verbosity = git_config_int(var, value);
                return 0;
        }
+       if (!strcasecmp(var, "diff.renamelimit")) {
+               rename_limit = git_config_int(var, value);
+               return 0;
+       }
        return git_default_config(var, value);
 }