[PATCH 7/8] gpg-interface: prepare for parsing arbitrary PEM blocks

[Ben Toews]

From: Jeff King <p...@peff.net>

In preparation for handling more PEM blocks besides "PGP
SIGNATURE" and "PGP MESSAGE', let's break up the parsing to
parameterize the actual block type.
---
 gpg-interface.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/gpg-interface.c b/gpg-interface.c
index 0647bd6348..0ba4a8ac3b 100644
--- a/gpg-interface.c
+++ b/gpg-interface.c
@@ -9,9 +9,6 @@
 static char *configured_signing_key;
 static const char *gpg_program = "gpg";
 
-#define PGP_SIGNATURE "-----BEGIN PGP SIGNATURE-----"
-#define PGP_MESSAGE "-----BEGIN PGP MESSAGE-----"
-
 void signature_check_clear(struct signature_check *sigc)
 {
        FREE_AND_NULL(sigc->payload);
@@ -101,10 +98,17 @@ void print_signature_buffer(const struct signature_check 
*sigc, unsigned flags)
                fputs(output, stderr);
 }
 
-static int is_gpg_start(const char *line)
+static int is_pem_start(const char *line)
 {
-       return starts_with(line, PGP_SIGNATURE) ||
-               starts_with(line, PGP_MESSAGE);
+       if (!skip_prefix(line, "-----BEGIN ", &line))
+               return 0;
+       if (!skip_prefix(line, "PGP SIGNATURE", &line) &&
+           !skip_prefix(line, "PGP MESSAGE", &line))
+               return 0;
+       if (!starts_with(line, "-----"))
+               return 0;
+
+       return 1;
 }
 
 size_t parse_signature(const char *buf, size_t size)
@@ -114,7 +118,7 @@ size_t parse_signature(const char *buf, size_t size)
        while (len < size) {
                const char *eol;
 
-               if (is_gpg_start(buf + len))
+               if (is_pem_start(buf + len))
                        match = len;
 
                eol = memchr(buf + len, '\n', size - len);
-- 
2.15.1 (Apple Git-101)