Make compare_packet follow memcmp semantics and export to other modules

  compare_packet is potentially useful elsewhere, but rather than a
  true/false comparison provide -1/0/1 for less than/equal/greater
  than, as memcmp does.

diff --git a/merge.c b/merge.c
index be97eb4782b32f5550f8f63a6db0db87d858c9ac..118e757737796871352c9ce2a2b421a2b5c19850 100644 (file)
--- a/merge.c
+++ b/merge.c
@@ -24,13 +24,26 @@
  *     @a: The first packet to compare.
  *     @b: The second packet to compare.
  *
- *     Takes 2 packets and returns true if they are the same and false
- *     otherwise.
+ *     Takes 2 packets and returns 0 if they are the same, -1 if a is
+ *      less than b, or 1 if a is greater than b.
  */
-bool compare_packets(struct openpgp_packet *a, struct openpgp_packet *b)
+int compare_packets(struct openpgp_packet *a, struct openpgp_packet *b)
 {
-       return (a->tag == b->tag && a->length == b->length &&
-               !memcmp(a->data, b->data, b->length));
+       int ret, len;
+
+       if (a->tag > b->tag) {
+               ret = 1;
+       } else if (b->tag > a->tag) {
+               ret = -1;
+       } else {
+               len = (a->length < b->length) ? a->length : b->length;
+               ret = memcmp(a->data, b->data, len);
+               if (ret == 0 && a->length != b->length) {
+                       ret = (a->length < b->length) ? -1 : 1;
+               }
+       }
+
+       return ret;
 }
 
 /**
@@ -73,7 +86,7 @@ bool find_packet(struct openpgp_packet_list *packet_list,
        bool found = false;
 
        while (!found && packet_list != NULL) {
-               if (compare_packets(packet_list->packet, packet)) {
+               if (compare_packets(packet_list->packet, packet) == 0) {
                        found = true;
                }
                packet_list = packet_list -> next;
@@ -122,7 +135,7 @@ struct openpgp_signedpacket_list *find_signed_packet(
        struct openpgp_signedpacket_list *found = NULL;
 
        while (found == NULL && packet_list != NULL) {
-               if (compare_packets(packet_list->packet, packet)) {
+               if (compare_packets(packet_list->packet, packet) == 0) {
                        found = packet_list;
                }
                packet_list = packet_list -> next;
@@ -149,7 +162,7 @@ bool remove_signed_packet(struct openpgp_signedpacket_list **packet_list,
        bool found = false;
 
        for (cur = *packet_list; !found && (cur != NULL); cur = cur->next) {
-               if (compare_packets(cur->packet, packet)) {
+               if (compare_packets(cur->packet, packet) == 0) {
                        found = true;
                        if (prev == NULL) {
                                *packet_list = cur->next;
@@ -186,7 +199,7 @@ int merge_packet_sigs(struct openpgp_signedpacket_list *old,
        struct openpgp_packet_list      *curpacket = NULL;
        struct openpgp_packet_list      *nextpacket = NULL;
 
-       log_assert(compare_packets(old->packet, new->packet));
+       log_assert(compare_packets(old->packet, new->packet) == 0);
 
        curpacket = new->sigs;
        while (curpacket != NULL) {

diff --git a/merge.h b/merge.h
index cabbc1886a35db8e26654690ba065b51f4185db7..770da9eee3f331fdcd00e25ddd0dcc765d7cef45 100644 (file)
--- a/merge.h
+++ b/merge.h
@@ -10,6 +10,16 @@
 
 #include "keystructs.h"
 
+/**
+ *     compare_packets - Check to see if 2 OpenPGP packets are the same.
+ *     @a: The first packet to compare.
+ *     @b: The second packet to compare.
+ *
+ *     Takes 2 packets and returns 0 if they are the same, -1 if a is
+ *      less than b, or 1 if a is greater than b.
+ */
+int compare_packets(struct openpgp_packet *a, struct openpgp_packet *b);
+
 /**
  *     merge_keys - Takes 2 public keys and merges them.
  *     @a: The old key. The merged key is returned in this structure.