add: support for forced versions

Support version numbers specified with packages. For example:

 apk add 'busybox<1.14'
 apk add 'squid=>3.0'

src/add.c

@@ -122,11 +122,7 @@ static int add_main(void *ctx, int argc, char **argv)
 		md5_str(virtpkg->name->name, virtpkg->csum);
 		virtpkg->version = strdup("0");
 		virtpkg->description = strdup("virtual meta package");
-		virtdep = (struct apk_dependency) {
-			.name = virtpkg->name,
-			.version = virtpkg->version,
-			.result_mask = APK_VERSION_EQUAL,
-		};
+		virtdep = apk_dep_from_pkg(&db, virtpkg);
 		virtdep.name->flags |= APK_NAME_TOPLEVEL | APK_NAME_VIRTUAL;
 		virtpkg = apk_db_pkg_add(&db, virtpkg);
 	}
@@ -143,17 +139,10 @@ static int add_main(void *ctx, int argc, char **argv)
 				goto err;
 			}
 
-			dep = (struct apk_dependency) {
-				.name = apk_db_get_name(&db, APK_BLOB_STR(pkg->name->name)),
-				.version = pkg->version,
-				.result_mask = APK_VERSION_EQUAL,
-			};
-		} else {
-			dep = (struct apk_dependency) {
-				.name = apk_db_get_name(&db, APK_BLOB_STR(argv[i])),
-				.result_mask = APK_DEPMASK_REQUIRE,
-			};
-		}
+			dep = apk_dep_from_pkg(&db, pkg);
+		} else
+			dep = apk_dep_from_str(&db, argv[i]);
+
 		if (virtpkg) {
 			apk_deps_add(&virtpkg->depends, &dep);
 		} else {

src/apk_package.h

@@ -94,4 +94,8 @@ int apk_pkg_run_script(struct apk_package *pkg, int root_fd,
 struct apk_package *apk_pkg_parse_index_entry(struct apk_database *db, apk_blob_t entry);
 int apk_pkg_write_index_entry(struct apk_package *pkg, struct apk_ostream *os);
 
+struct apk_dependency apk_dep_from_str(struct apk_database *db,
+				       char *str);
+struct apk_dependency apk_dep_from_pkg(struct apk_database *db,
+				       struct apk_package *pkg);
 #endif

src/apk_version.h

@@ -19,6 +19,7 @@
 #define APK_VERSION_GREATER		4
 
 const char *apk_version_op_string(int result_mask);
+int apk_version_result_mask(const char *str);
 int apk_version_validate(apk_blob_t ver);
 int apk_version_compare(apk_blob_t a, apk_blob_t b);
 

src/package.c

@@ -663,3 +663,36 @@ int apk_pkg_write_index_entry(struct apk_package *info,
 
 	return n;
 }
+
+struct apk_dependency apk_dep_from_str(struct apk_database *db,
+				       char *str)
+{
+	apk_blob_t name = APK_BLOB_STR(str);
+	char *v = str;
+	int mask = APK_DEPMASK_REQUIRE;
+
+	v = strpbrk(str, "<>=");
+	if (v != NULL) {
+		name.len = v - str;
+		mask = apk_version_result_mask(v++);
+		if (*v == '=')
+			v++;
+	} 
+	printf("DEBUG: result_mask = %x\n", mask);
+	return (struct apk_dependency) {
+		.name = apk_db_get_name(db, name),
+		.version = v,
+		.result_mask = mask,
+	};
+}
+
+struct apk_dependency apk_dep_from_pkg(struct apk_database *db,
+				       struct apk_package *pkg)
+{
+	return (struct apk_dependency) {
+		.name = apk_db_get_name(db, APK_BLOB_STR(pkg->name->name)),
+		.version = pkg->version,
+		.result_mask = APK_VERSION_EQUAL,
+	};
+}
+

src/version.c

@@ -146,6 +146,24 @@ const char *apk_version_op_string(int mask)
 	}
 }
 
+int apk_version_result_mask(const char *str)
+{
+	int r = 0;
+	switch (*str) {
+	case '<':
+		r = APK_VERSION_LESS;
+		str++;
+		break;
+	case '>':
+		r = APK_VERSION_GREATER;
+		str++;
+		break;
+	}
+	if (*str ==  '=')
+		r |= APK_VERSION_EQUAL;
+	return r;
+}			
+
 int apk_version_validate(apk_blob_t ver)
 {
 	int t = TOKEN_DIGIT;