Allow alpm_depend_t to have a description

This is the first step in parsing and handling optdepends. There is no
behavior change introduced in this commit; however, depends that contain
a ": " string will now be parsed as having a description and it will be
stored in the depend structure. Later patches will utilize this new
field as appropriate.

This is heavily based on the work of Benedikt, who did something similar
but introduced a new type for this rather than only a new field to the
existing type.

Heavily-influenced-by: Benedikt Morbach <benedikt.morbach@googlemail.com>
Signed-off-by: Dan McGee <dan@archlinux.org>

2 files changed, 32 insertions, 13 deletions

diff --git a/lib/libalpm/alpm.h b/lib/libalpm/alpm.h
index 5f587d38..8a418dc0 100644
--- a/lib/libalpm/alpm.h
+++ b/lib/libalpm/alpm.h
@@ -136,6 +136,7 @@ typedef struct __alpm_trans_t alpm_trans_t;
 typedef struct _alpm_depend_t {
 	char *name;
 	char *version;
+	char *desc;
 	unsigned long name_hash;
 	alpm_depmod_t mod;
 } alpm_depend_t;
diff --git a/lib/libalpm/deps.c b/lib/libalpm/deps.c
index eda0648d..6069f5e6 100644
--- a/lib/libalpm/deps.c
+++ b/lib/libalpm/deps.c
@@ -39,6 +39,7 @@ void _alpm_dep_free(alpm_depend_t *dep)
 {
 	FREE(dep->name);
 	FREE(dep->version);
+	FREE(dep->desc);
 	FREE(dep);
 }
 
@@ -409,7 +410,7 @@ int _alpm_depcmp(alpm_pkg_t *pkg, alpm_depend_t *dep)
 alpm_depend_t *_alpm_splitdep(const char *depstring)
 {
 	alpm_depend_t *depend;
-	const char *ptr, *version;
+	const char *ptr, *version, *desc;
 	size_t deplen;
 
 	if(depstring == NULL) {
@@ -417,7 +418,17 @@ alpm_depend_t *_alpm_splitdep(const char *depstring)
 	}
 
 	MALLOC(depend, sizeof(alpm_depend_t), return NULL);
-	deplen = strlen(depstring);
+
+	/* Note the extra space in ": " to avoid matching the epoch */
+	if((desc = strstr(depstring, ": ")) != NULL) {
+		STRDUP(depend->desc, desc + 2, return NULL);
+		deplen = desc - depstring;
+	} else {
+		/* no description- point desc at NULL at end of string for later use */
+		depend->desc = NULL;
+		deplen = strlen(depstring);
+		desc = depstring + deplen;
+	}
 
 	/* Find a version comparator if one exists. If it does, set the type and
 	 * increment the ptr accordingly so we can copy the right strings. */
@@ -442,21 +453,18 @@ alpm_depend_t *_alpm_splitdep(const char *depstring)
 		depend->mod = ALPM_DEP_MOD_EQ;
 		version = ptr + 1;
 	} else {
-		/* no version specified, leave ptr NULL and set version to NULL */
+		/* no version specified, set ptr to end of string and version to NULL */
+		ptr = depstring + deplen;
 		depend->mod = ALPM_DEP_MOD_ANY;
 		depend->version = NULL;
 		version = NULL;
 	}
 
 	/* copy the right parts to the right places */
-	if(ptr) {
-		STRNDUP(depend->name, depstring, ptr - depstring, return NULL);
-	} else {
-		STRDUP(depend->name, depstring, return NULL);
-	}
+	STRNDUP(depend->name, depstring, ptr - depstring, return NULL);
 	depend->name_hash = _alpm_hash_sdbm(depend->name);
 	if(version) {
-		STRDUP(depend->version, version, return NULL);
+		STRNDUP(depend->version, version, desc - version, return NULL);
 	}
 
 	return depend;
@@ -468,8 +476,9 @@ alpm_depend_t *_alpm_dep_dup(const alpm_depend_t *dep)
 	CALLOC(newdep, 1, sizeof(alpm_depend_t), return NULL);
 
 	STRDUP(newdep->name, dep->name, return NULL);
-	newdep->name_hash = dep->name_hash;
 	STRDUP(newdep->version, dep->version, return NULL);
+	STRDUP(newdep->desc, dep->desc, return NULL);
+	newdep->name_hash = dep->name_hash;
 	newdep->mod = dep->mod;
 
 	return newdep;
@@ -792,7 +801,7 @@ int _alpm_resolvedeps(alpm_handle_t *handle, alpm_list_t *localpkgs,
  */
 char SYMEXPORT *alpm_dep_compute_string(const alpm_depend_t *dep)
 {
-	const char *name, *opr, *ver;
+	const char *name, *opr, *ver, *desc_delim, *desc;
 	char *str;
 	size_t len;
 
@@ -834,12 +843,21 @@ char SYMEXPORT *alpm_dep_compute_string(const alpm_depend_t *dep)
 		ver = "";
 	}
 
+	if(dep->desc) {
+		desc_delim = ": ";
+		desc = dep->desc;
+	} else {
+		desc_delim = "";
+		desc = "";
+	}
+
 	/* we can always compute len and print the string like this because opr
 	 * and ver will be empty when ALPM_DEP_MOD_ANY is the depend type. the
 	 * reassignments above also ensure we do not do a strlen(NULL). */
-	len = strlen(name) + strlen(opr) + strlen(ver) + 1;
+	len = strlen(name) + strlen(opr) + strlen(ver)
+		+ strlen(desc_delim) + strlen(desc) + 1;
 	MALLOC(str, len, return NULL);
-	snprintf(str, len, "%s%s%s", name, opr, ver);
+	snprintf(str, len, "%s%s%s%s%s", name, opr, ver, desc_delim, desc);
 
 	return str;
 }