[PATCH] Custom low-level merge driver: change the configuration scheme.
Show changes to 2 files +131 −79
merge-recursive.c, t/t6026-merge-attr.sh
diff --git a/merge-recursive.c b/merge-recursive.c
index 5983000..4af69d7 100644
--- a/merge-recursive.c
+++ b/merge-recursive.c
@@ -661,14 +661,31 @@ static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
mm->size = size;
}
-/* Low-level merge functions */
-typedef int (*ll_merge_fn)(const char *cmd,
+/*
+ * 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);
-static int ll_xdl_merge(const char *cmd__unused,
+struct ll_merge_driver {
+ const char *name;
+ const char *description;
+ ll_merge_fn fn;
+ struct ll_merge_driver *next;
+ char *cmdline;
+};
+
+/*
+ * Built-in low-levels
+ */
+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,
@@ -684,7 +701,8 @@ static int ll_xdl_merge(const char *cmd__unused,
result);
}
-static int ll_union_merge(const char *cmd__unused,
+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,
@@ -694,8 +712,8 @@ static int ll_union_merge(const char *cmd__unused,
long size;
const int marker_size = 7;
- int status = ll_xdl_merge(cmd__unused, orig,
- src1, NULL, src2, NULL, result);
+ int status = ll_xdl_merge(drv_unused, path_unused,
+ orig, src1, NULL, src2, NULL, result);
if (status <= 0)
return status;
size = result->size;
@@ -726,7 +744,8 @@ static int ll_union_merge(const char *cmd__unused,
return 0;
}
-static int ll_binary_merge(const char *cmd__unused,
+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,
@@ -745,14 +764,13 @@ static int ll_binary_merge(const char *cmd__unused,
return 1;
}
-static struct {
- const char *name;
- ll_merge_fn fn;
-} ll_merge_fns[] = {
- { "binary", ll_binary_merge },
- { "text", ll_xdl_merge },
- { "union", ll_union_merge },
- { NULL, NULL },
+#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)
@@ -768,7 +786,11 @@ static void create_temp(mmfile_t *src, char *path)
close(fd);
}
-static int ll_ext_merge(const char *cmd,
+/*
+ * 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,
@@ -796,7 +818,10 @@ static int ll_ext_merge(const char *cmd,
interp_set_entry(table, 1, temp[1]);
interp_set_entry(table, 2, temp[2]);
- interpolate(cmdbuf, sizeof(cmdbuf), cmd, table, 3);
+ 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;
@@ -833,101 +858,124 @@ static int ll_ext_merge(const char *cmd,
/*
* merge.default and merge.driver configuration items
*/
-static struct user_merge_fn {
- struct user_merge_fn *next;
- const char *name;
- char *cmdline;
- char b_[1];
-} *ll_user_merge_fns, **ll_user_merge_fns_tail;
+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 user_merge_fn *fn;
- int blen, nlen;
+ struct ll_merge_driver *fn;
+ const char *ep, *name;
+ int namelen;
if (!strcmp(var, "merge.default")) {
- default_ll_merge = strdup(value);
+ if (value)
+ default_ll_merge = strdup(value);
return 0;
}
- if (strcmp(var, "merge.driver"))
+ /*
+ * 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 = strchr(var + 6, '.')) == NULL)
return 0;
- if (!value)
- return error("%s: lacks value", var);
+
/*
- * merge.driver is a multi-valued configuration, whose value is
- * of form:
- *
- * name 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 exit status 0.
+ * Find existing one as we might be processing merge.<name>.var2
+ * after seeing merge.<name>.var1.
*/
- for (nlen = -1, blen = 0; value[blen]; blen++)
- if (nlen < 0 && isspace(value[blen]))
- nlen = blen;
- if (nlen < 0)
- return error("%s '%s': lacks command line", var, value);
- fn = xcalloc(1, sizeof(struct user_merge_fn) + blen + 1);
- memcpy(fn->b_, value, blen + 1);
- fn->name = fn->b_;
- fn->b_[nlen] = 0;
- fn->cmdline = fn->b_ + nlen + 1;
- fn->next = *ll_user_merge_fns_tail;
- *ll_user_merge_fns_tail = fn;
+ 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) {
+ char *namebuf;
+ fn = xcalloc(1, sizeof(struct ll_merge_driver));
+ namebuf = xmalloc(namelen + 1);
+ memcpy(namebuf, name, namelen);
+ namebuf[namelen] = 0;
+ fn->name = namebuf;
+ fn->fn = ll_ext_merge;
+ fn->next = *ll_user_merge_tail;
+ *ll_user_merge_tail = fn;
+ }
+
+ 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;
+ }
+
return 0;
}
static void initialize_ll_merge(void)
{
- if (ll_user_merge_fns_tail)
+ if (ll_user_merge_tail)
return;
- ll_user_merge_fns_tail = &ll_user_merge_fns;
+ ll_user_merge_tail = &ll_user_merge;
git_config(read_merge_config);
}
-static ll_merge_fn find_ll_merge_fn(void *merge_attr, const char **cmdline)
+static const struct ll_merge_driver *find_ll_merge_driver(void *merge_attr)
{
- struct user_merge_fn *fn;
+ struct ll_merge_driver *fn;
const char *name;
int i;
initialize_ll_merge();
if (ATTR_TRUE(merge_attr))
- return ll_xdl_merge;
+ return &ll_merge_drv[LL_TEXT_MERGE];
else if (ATTR_FALSE(merge_attr))
- return ll_binary_merge;
+ return &ll_merge_drv[LL_BINARY_MERGE];
else if (ATTR_UNSET(merge_attr)) {
if (!default_ll_merge)
- return ll_xdl_merge;
+ return &ll_merge_drv[LL_TEXT_MERGE];
else
name = default_ll_merge;
}
else
name = merge_attr;
- for (fn = ll_user_merge_fns; fn; fn = fn->next) {
- if (!strcmp(fn->name, name)) {
- *cmdline = fn->cmdline;
- return ll_ext_merge;
- }
- }
+ for (fn = ll_user_merge; fn; fn = fn->next)
+ if (!strcmp(fn->name, name))
+ return fn;
- for (i = 0; ll_merge_fns[i].name; i++)
- if (!strcmp(ll_merge_fns[i].name, name))
- return ll_merge_fns[i].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_xdl_merge;
+ return &ll_merge_drv[LL_TEXT_MERGE];
}
static void *git_path_check_merge(const char *path)
@@ -953,8 +1001,7 @@ static int ll_merge(mmbuffer_t *result_buf,
char *name1, *name2;
int merge_status;
void *merge_attr;
- ll_merge_fn fn;
- const char *driver = NULL;
+ const struct ll_merge_driver *driver;
name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
@@ -964,10 +1011,11 @@ static int ll_merge(mmbuffer_t *result_buf,
fill_mm(b->sha1, &src2);
merge_attr = git_path_check_merge(a->path);
- fn = find_ll_merge_fn(merge_attr, &driver);
+ driver = find_ll_merge_driver(merge_attr);
- merge_status = fn(driver, &orig,
- &src1, name1, &src2, name2, result_buf);
+ merge_status = driver->fn(driver, a->path,
+ &orig, &src1, name1, &src2, name2,
+ result_buf);
free(name1);
free(name2);
diff --git a/t/t6026-merge-attr.sh b/t/t6026-merge-attr.sh
index 1732b60..56fc341 100755
--- a/t/t6026-merge-attr.sh
+++ b/t/t6026-merge-attr.sh
@@ -98,7 +98,9 @@ test_expect_success 'custom merge backend' '
git reset --hard anchor &&
git config --replace-all \
- merge.driver "custom ./custom-merge %O %A %B 0" &&
+ merge.custom.driver "./custom-merge %O %A %B 0" &&
+ git config --replace-all \
+ merge.custom.name "custom merge driver for testing" &&
git merge master &&
@@ -117,7 +119,9 @@ test_expect_success 'custom merge backend' '
git reset --hard anchor &&
git config --replace-all \
- merge.driver "custom ./custom-merge %O %A %B 1" &&
+ merge.custom.driver "./custom-merge %O %A %B 1" &&
+ git config --replace-all \
+ merge.custom.name "custom merge driver for testing" &&
if git merge master
then
Junio C Hamano
