pathspec: move long magic parsing out of prefix_pathspec

`prefix_pathspec` is quite a lengthy function and we plan on adding more.
Split it up for better readability. As we want to add code into the
inner loop of the long magic parsing, we also benefit from lower
indentation.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 47 insertions, 37 deletions

diff --git a/pathspec.c b/pathspec.c
index c9e9b6c077..eba37c2ec1 100644
--- a/pathspec.c
+++ b/pathspec.c
@@ -88,6 +88,52 @@ static void prefix_short_magic(struct strbuf *sb, int prefixlen,
 	strbuf_addf(sb, ",prefix:%d)", prefixlen);
 }
 
+static void eat_long_magic(struct pathspec_item *item, const char *elt,
+		unsigned *magic, int *pathspec_prefix,
+		const char **copyfrom_, const char **long_magic_end)
+{
+	int i;
+	const char *copyfrom = *copyfrom_;
+	/* longhand */
+	const char *nextat;
+	for (copyfrom = elt + 2;
+	     *copyfrom && *copyfrom != ')';
+	     copyfrom = nextat) {
+		size_t len = strcspn(copyfrom, ",)");
+		if (copyfrom[len] == ',')
+			nextat = copyfrom + len + 1;
+		else
+			/* handle ')' and '\0' */
+			nextat = copyfrom + len;
+		if (!len)
+			continue;
+		for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++) {
+			if (strlen(pathspec_magic[i].name) == len &&
+			    !strncmp(pathspec_magic[i].name, copyfrom, len)) {
+				*magic |= pathspec_magic[i].bit;
+				break;
+			}
+			if (starts_with(copyfrom, "prefix:")) {
+				char *endptr;
+				*pathspec_prefix = strtol(copyfrom + 7,
+							  &endptr, 10);
+				if (endptr - copyfrom != len)
+					die(_("invalid parameter for pathspec magic 'prefix'"));
+				/* "i" would be wrong, but it does not matter */
+				break;
+			}
+		}
+		if (ARRAY_SIZE(pathspec_magic) <= i)
+			die(_("Invalid pathspec magic '%.*s' in '%s'"),
+			    (int) len, copyfrom, elt);
+	}
+	if (*copyfrom != ')')
+		die(_("Missing ')' at the end of pathspec magic in '%s'"), elt);
+	*long_magic_end = copyfrom;
+	copyfrom++;
+	*copyfrom_ = copyfrom;
+}
+
 /*
  * Take an element of a pathspec and check for magic signatures.
  * Append the result to the prefix. Return the magic bitmap.
@@ -150,43 +196,7 @@ static unsigned prefix_pathspec(struct pathspec_item *item,
 	    (flags & PATHSPEC_LITERAL_PATH)) {
 		; /* nothing to do */
 	} else if (elt[1] == '(') {
-		/* longhand */
-		const char *nextat;
-		for (copyfrom = elt + 2;
-		     *copyfrom && *copyfrom != ')';
-		     copyfrom = nextat) {
-			size_t len = strcspn(copyfrom, ",)");
-			if (copyfrom[len] == ',')
-				nextat = copyfrom + len + 1;
-			else
-				/* handle ')' and '\0' */
-				nextat = copyfrom + len;
-			if (!len)
-				continue;
-			for (i = 0; i < ARRAY_SIZE(pathspec_magic); i++) {
-				if (strlen(pathspec_magic[i].name) == len &&
-				    !strncmp(pathspec_magic[i].name, copyfrom, len)) {
-					magic |= pathspec_magic[i].bit;
-					break;
-				}
-				if (starts_with(copyfrom, "prefix:")) {
-					char *endptr;
-					pathspec_prefix = strtol(copyfrom + 7,
-								 &endptr, 10);
-					if (endptr - copyfrom != len)
-						die(_("invalid parameter for pathspec magic 'prefix'"));
-					/* "i" would be wrong, but it does not matter */
-					break;
-				}
-			}
-			if (ARRAY_SIZE(pathspec_magic) <= i)
-				die(_("Invalid pathspec magic '%.*s' in '%s'"),
-				    (int) len, copyfrom, elt);
-		}
-		if (*copyfrom != ')')
-			die(_("Missing ')' at the end of pathspec magic in '%s'"), elt);
-		long_magic_end = copyfrom;
-		copyfrom++;
+		eat_long_magic(item, elt, &magic, &pathspec_prefix, &copyfrom, &long_magic_end);
 	} else {
 		/* shorthand */
 		for (copyfrom = elt + 1;