dir: allow exclusions from blob in addition to file

Refactor add_excludes() to separate the reading of the
exclude file into a buffer and the parsing of the buffer
into exclude_list items.

Add add_excludes_from_blob_to_list() to allow an exclude
file be specified with an OID without assuming a local
worktree or index exists.

Refactor read_skip_worktree_file_from_index() and add
do_read_blob() to eliminate duplication of preliminary
processing of blob contents.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>
Reviewed-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/dir.c b/dir.c
index 1d17b800cf374d179d7cef3c6bbb180a5a1b4aba..1962374d2ae6e0e5746623e96a8c3ad74d503b5d 100644 (file)
--- a/dir.c
+++ b/dir.c
@@ -220,6 +220,57 @@ int within_depth(const char *name, int namelen,
        return 1;
 }
 
+/*
+ * Read the contents of the blob with the given OID into a buffer.
+ * Append a trailing LF to the end if the last line doesn't have one.
+ *
+ * Returns:
+ *    -1 when the OID is invalid or unknown or does not refer to a blob.
+ *     0 when the blob is empty.
+ *     1 along with { data, size } of the (possibly augmented) buffer
+ *       when successful.
+ *
+ * Optionally updates the given sha1_stat with the given OID (when valid).
+ */
+static int do_read_blob(const struct object_id *oid,
+                       struct sha1_stat *sha1_stat,
+                       size_t *size_out,
+                       char **data_out)
+{
+       enum object_type type;
+       unsigned long sz;
+       char *data;
+
+       *size_out = 0;
+       *data_out = NULL;
+
+       data = read_sha1_file(oid->hash, &type, &sz);
+       if (!data || type != OBJ_BLOB) {
+               free(data);
+               return -1;
+       }
+
+       if (sha1_stat) {
+               memset(&sha1_stat->stat, 0, sizeof(sha1_stat->stat));
+               hashcpy(sha1_stat->sha1, oid->hash);
+       }
+
+       if (sz == 0) {
+               free(data);
+               return 0;
+       }
+
+       if (data[sz - 1] != '\n') {
+               data = xrealloc(data, st_add(sz, 1));
+               data[sz++] = '\n';
+       }
+
+       *size_out = xsize_t(sz);
+       *data_out = data;
+
+       return 1;
+}
+
 #define DO_MATCH_EXCLUDE   (1<<0)
 #define DO_MATCH_DIRECTORY (1<<1)
 #define DO_MATCH_SUBMODULE (1<<2)
@@ -600,32 +651,22 @@ void add_exclude(const char *string, const char *base,
        x->el = el;
 }
 
-static void *read_skip_worktree_file_from_index(const struct index_state *istate,
-                                               const char *path, size_t *size,
-                                               struct sha1_stat *sha1_stat)
+static int read_skip_worktree_file_from_index(const struct index_state *istate,
+                                             const char *path,
+                                             size_t *size_out,
+                                             char **data_out,
+                                             struct sha1_stat *sha1_stat)
 {
        int pos, len;
-       unsigned long sz;
-       enum object_type type;
-       void *data;
 
        len = strlen(path);
        pos = index_name_pos(istate, path, len);
        if (pos < 0)
-               return NULL;
+               return -1;
        if (!ce_skip_worktree(istate->cache[pos]))
-               return NULL;
-       data = read_sha1_file(istate->cache[pos]->oid.hash, &type, &sz);
-       if (!data || type != OBJ_BLOB) {
-               free(data);
-               return NULL;
-       }
-       *size = xsize_t(sz);
-       if (sha1_stat) {
-               memset(&sha1_stat->stat, 0, sizeof(sha1_stat->stat));
-               hashcpy(sha1_stat->sha1, istate->cache[pos]->oid.hash);
-       }
-       return data;
+               return -1;
+
+       return do_read_blob(&istate->cache[pos]->oid, sha1_stat, size_out, data_out);
 }
 
 /*
@@ -739,6 +780,10 @@ static void invalidate_directory(struct untracked_cache *uc,
                dir->dirs[i]->recurse = 0;
 }
 
+static int add_excludes_from_buffer(char *buf, size_t size,
+                                   const char *base, int baselen,
+                                   struct exclude_list *el);
+
 /*
  * Given a file with name "fname", read it (either from disk, or from
  * an index if 'istate' is non-null), parse it and store the
@@ -754,9 +799,10 @@ static int add_excludes(const char *fname, const char *base, int baselen,
                        struct sha1_stat *sha1_stat)
 {
        struct stat st;
-       int fd, i, lineno = 1;
+       int r;
+       int fd;
        size_t size = 0;
-       char *buf, *entry;
+       char *buf;
 
        fd = open(fname, O_RDONLY);
        if (fd < 0 || fstat(fd, &st) < 0) {
@@ -764,17 +810,13 @@ static int add_excludes(const char *fname, const char *base, int baselen,
                        warn_on_fopen_errors(fname);
                else
                        close(fd);
-               if (!istate ||
-                   (buf = read_skip_worktree_file_from_index(istate, fname, &size, sha1_stat)) == NULL)
+               if (!istate)
                        return -1;
-               if (size == 0) {
-                       free(buf);
-                       return 0;
-               }
-               if (buf[size-1] != '\n') {
-                       buf = xrealloc(buf, st_add(size, 1));
-                       buf[size++] = '\n';
-               }
+               r = read_skip_worktree_file_from_index(istate, fname,
+                                                      &size, &buf,
+                                                      sha1_stat);
+               if (r != 1)
+                       return r;
        } else {
                size = xsize_t(st.st_size);
                if (size == 0) {
@@ -813,6 +855,17 @@ static int add_excludes(const char *fname, const char *base, int baselen,
                }
        }
 
+       add_excludes_from_buffer(buf, size, base, baselen, el);
+       return 0;
+}
+
+static int add_excludes_from_buffer(char *buf, size_t size,
+                                   const char *base, int baselen,
+                                   struct exclude_list *el)
+{
+       int i, lineno = 1;
+       char *entry;
+
        el->filebuf = buf;
 
        if (skip_utf8_bom(&buf, size))
@@ -841,6 +894,23 @@ int add_excludes_from_file_to_list(const char *fname, const char *base,
        return add_excludes(fname, base, baselen, el, istate, NULL);
 }
 
+int add_excludes_from_blob_to_list(
+       struct object_id *oid,
+       const char *base, int baselen,
+       struct exclude_list *el)
+{
+       char *buf;
+       size_t size;
+       int r;
+
+       r = do_read_blob(oid, NULL, &size, &buf);
+       if (r != 1)
+               return r;
+
+       add_excludes_from_buffer(buf, size, base, baselen, el);
+       return 0;
+}
+
 struct exclude_list *add_exclude_list(struct dir_struct *dir,
                                      int group_type, const char *src)
 {

diff --git a/dir.h b/dir.h
index e3717055d193366e6780b50d68f6a3c2360d32c4..1bcf39123ad7fd46c875a26a9f54569c3a3a9f89 100644 (file)
--- a/dir.h
+++ b/dir.h
@@ -256,6 +256,9 @@ extern struct exclude_list *add_exclude_list(struct dir_struct *dir,
 extern int add_excludes_from_file_to_list(const char *fname, const char *base, int baselen,
                                          struct exclude_list *el, struct  index_state *istate);
 extern void add_excludes_from_file(struct dir_struct *, const char *fname);
+extern int add_excludes_from_blob_to_list(struct object_id *oid,
+                                         const char *base, int baselen,
+                                         struct exclude_list *el);
 extern void parse_exclude_pattern(const char **string, int *patternlen, unsigned *flags, int *nowildcardlen);
 extern void add_exclude(const char *string, const char *base,
                        int baselen, struct exclude_list *el, int srcpos);