From e68c00d7e00a330be5ca6cf249ae3476a06bfa2f Mon Sep 17 00:00:00 2001
From: Paweł Redman <pawel.redman@gmail.com>
Date: Tue, 20 Dec 2016 10:48:53 +0100
Subject: Refactor mapcat.c to get rid of globals.

---
 src/common.h |  46 +++++++-
 src/elist.h  |  14 ++-
 src/main.c   |  34 +++++-
 src/mapcat.c | 334 ++++++++++++++++++++++++++++++++---------------------------
 4 files changed, 267 insertions(+), 161 deletions(-)

diff --git a/src/common.h b/src/common.h
index 8c6f43f..7420485 100644
--- a/src/common.h
+++ b/src/common.h
@@ -33,6 +33,8 @@ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 #define PROGRAM_NAME "mapcat"
 #define PROGRAM_VERSION "0.1.0"
 
+#define MAPCAT_DISCARD_SHADER "common/discard"
+
 // common.c
 
 typedef struct {
@@ -81,6 +83,44 @@ int lexer_get_floats(lexer_state_t *ls, float *out, size_t count);
 
 // mapcat.c
 
-int mapcat_load(const char *path);
-int mapcat_save(const char *path);
-void mapcat_free(void);
+typedef struct {
+	float def[9];
+	char *shader;
+	float texmap[8];
+	elist_header_t list;
+} brush_face_t;
+
+typedef struct {
+	brush_face_t *faces;
+	elist_header_t list;
+} brush_t;
+
+typedef struct {
+	char *key;
+	char *value;
+	elist_header_t list;
+} entity_key_t;
+
+typedef struct {
+	char *classname;
+	brush_t *brushes;
+	entity_key_t *keys;
+
+	elist_header_t list;
+} entity_t;
+
+typedef struct {
+	entity_t *worldspawn;
+	entity_t *entities;
+
+	// note: num_entities doesn't include the worldspawn
+	size_t num_entities, num_discarded_entities;
+	size_t num_brushes, num_discarded_brushes;
+} map_t;
+
+void map_init(map_t *map);
+void map_free(map_t *map);
+int map_read(map_t *map, const char *path);
+int map_write(const map_t *map, const char *path);
+int map_merge(map_t *master, map_t *slave);
+void map_print_stats(const char *path, const map_t *map);
diff --git a/src/elist.h b/src/elist.h
index da6d172..84b2a72 100644
--- a/src/elist.h
+++ b/src/elist.h
@@ -27,6 +27,11 @@ static inline elist_header_t *elist_header(void *entry, size_t offs)
 	return (elist_header_t*)((char*)entry + offs);
 }
 
+static inline const elist_header_t *elist_cheader(const void *entry, size_t offs)
+{
+	return (const elist_header_t*)((const char*)entry + offs);
+}
+
 static inline void elist_append_real(void **head, void *entry, size_t offs)
 {
 	elist_header_t *head_header, *entry_header;
@@ -56,9 +61,15 @@ elist_append_real((void**)(head), (entry), offsetin((entry), member))
 #define elist_next(entry, member) \
 (elist_header((entry), offsetin((entry), member))->next)
 
+#define elist_cnext(entry, member) \
+(elist_cheader((entry), offsetin((entry), member))->next)
+
 #define elist_for(iter, head, member) \
 for ((iter) = (head); (iter); (iter) = elist_next((iter), member))
 
+#define elist_cfor(iter, head, member) \
+for ((iter) = (head); (iter); (iter) = elist_cnext((iter), member))
+
 static inline void elist_unlink_real(void **head, void *entry, size_t offs)
 {
 	elist_header_t *entry_header;
@@ -101,9 +112,10 @@ static inline void elist_append_list_real(void **head1, void *head2, size_t offs
 	if (!head2)
 		return;
 
-	head1_header = elist_header(head1, offs);
+	head1_header = elist_header(*head1, offs);
 	head2_header = elist_header(head2, offs);
 	last1_header = elist_header(head1_header->prev, offs);
+
 	head1_header->prev = head2_header->prev;
 	last1_header->next = head2;
 	head2_header->prev = head1_header->prev;
diff --git a/src/main.c b/src/main.c
index d34f00e..93cc0b0 100644
--- a/src/main.c
+++ b/src/main.c
@@ -47,6 +47,7 @@ int main(int argc, char **argv)
 	int rv = 1, i;
 	input_file_t *inputs = NULL, *input, *next;
 	char *output = NULL;
+	map_t map;
 
 	for (i = 1; i < argc; i++) {
 		if (!strcmp(argv[i], "-v")) {
@@ -92,17 +93,40 @@ int main(int argc, char **argv)
 		goto out;
 	}
 
-	elist_for (input, inputs, list)
-		if (mapcat_load(input->path))
+	map_init(&map);
+
+	elist_for (input, inputs, list) {
+		map_t part;
+
+		map_init(&part);
+
+		if (map_read(&part, input->path)) {
+			error("error: couldn't read %s\n", input->path);
+			goto out;
+		}
+
+		map_print_stats(input->path, &part);
+
+		if (map_merge(&map, &part)) {
+			error("error: couldn't merge %s into %s\n",
+			      input->path, output);
+			map_free(&map);
+			map_free(&part);
 			goto out;
+		}
+	}
 
-	if (mapcat_save(output))
+	map_print_stats(output, &map);
+
+	if (map_write(&map, output)) {
+		error("error: couldn't write %s\n", output);
+		map_free(&map);
 		goto out;
+	}
 
+	map_free(&map);
 	rv = 0;
 out:
-	mapcat_free();
-
 	for (input = inputs; input; input = next) {
 		next = elist_next(input, list);
 		free(input);
diff --git a/src/mapcat.c b/src/mapcat.c
index 6420cf5..d9bff86 100644
--- a/src/mapcat.c
+++ b/src/mapcat.c
@@ -19,34 +19,56 @@ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301  USA
 #define DEBUG
 #include "common.h"
 
-typedef struct {
-	float def[9];
-	char *shader;
-	float texmap[8];
-	elist_header_t list;
-} brush_face_t;
-
-typedef struct {
-	brush_face_t *faces;
-	elist_header_t list;
-} brush_t;
-
-typedef struct {
-	char *key;
-	char *value;
-	elist_header_t list;
-} entity_key_t;
-
-typedef struct {
-	char *classname;
-	brush_t *brushes;
-	entity_key_t *keys;
-
-	elist_header_t list;
-} entity_t;
-
-entity_t *worldspawn;
-entity_t *entities;
+//
+// freeing
+//
+
+static void free_entity_keys(entity_t *entity)
+{
+	entity_key_t *key, *next;
+
+	for (key = entity->keys; key; key = next) {
+		next = elist_next(key, list);
+
+		free(key->key);
+		free(key->value);
+		free(key);
+	}
+}
+
+static void free_brush(brush_t *brush)
+{
+	brush_face_t *face, *face_next;
+
+	for (face = brush->faces; face; face = face_next) {
+		face_next = elist_next(face, list);
+
+		free(face->shader);
+		free(face);
+	}
+
+	free(brush);
+}
+
+// this frees an entity_t and its children
+static void free_entity(entity_t *entity)
+{
+	brush_t *brush, *next;
+
+	free_entity_keys(entity);
+	free(entity->classname);
+
+	for (brush = entity->brushes; brush; brush = next) {
+		next = elist_next(brush, list);
+		free_brush(brush);
+	}
+
+	free(entity);
+}
+
+//
+// reading
+//
 
 static int read_entity_key(lexer_state_t *ls, entity_t *entity)
 {
@@ -174,79 +196,18 @@ static int read_brush_faces(lexer_state_t *ls, brush_t *brush)
 	return 0;
 }
 
-static void free_entity_keys(entity_t *entity)
-{
-	entity_key_t *key, *next;
-
-	for (key = entity->keys; key; key = next) {
-		next = elist_next(key, list);
-
-		free(key->key);
-		free(key->value);
-		free(key);
-	}
-}
-
-static void free_brush(brush_t *brush)
-{
-	brush_face_t *face, *face_next;
-
-	for (face = brush->faces; face; face = face_next) {
-		face_next = elist_next(face, list);
-
-		free(face->shader);
-		free(face);
-	}
-
-	free(brush);
-}
-
-// this frees an entity_t and its children
-// note: this function does NOT unlink the entity from the global list
-static void free_entity(entity_t *entity)
-{
-	brush_t *brush, *next;
-
-	free_entity_keys(entity);
-	free(entity->classname);
-
-	for (brush = entity->brushes; brush; brush = next) {
-		next = elist_next(brush, list);
-		free_brush(brush);
-	}
-
-	free(entity);
-}
-
-static void merge_into_worldspawn(entity_t *entity)
-{
-	// the first worldspawn becomes the output's worldspawn.
-	// other worldspawn's brushes are appended to it
-	if (!worldspawn) {
-		worldspawn = entity;
-		return;
-	}
-
-	// keep only the original key-value pairs
-	free_entity_keys(entity);
-
-	elist_append_list(worldspawn->brushes, entity->brushes, list);
-
-	free(entity);
-}
-
 static bool brush_discard(brush_t *brush)
 {
 	brush_face_t *face;
 
 	elist_for(face, brush->faces, list)
-		if (!strcmp(face->shader, "mapcat_discard"))
+		if (!strcmp(face->shader, MAPCAT_DISCARD_SHADER))
 			return true;
 
 	return false;
 }
 
-static int read_entity(lexer_state_t *ls)
+static int read_entity(lexer_state_t *ls, map_t *map)
 {
 	entity_t *entity;
 
@@ -311,18 +272,26 @@ static int read_entity(lexer_state_t *ls)
 			goto error;
 		}
 
-		if (brush_discard(brush))
+		if (brush_discard(brush)) {
 			free_brush(brush);
-		else
+			map->num_discarded_brushes++;
+		} else {
 			elist_append(&entity->brushes, brush, list);
+			map->num_brushes++;
+		}
 	}
 
 no_brushes:
+	if (!strcmp(entity->classname, "worldspawn")) {
+		if (map->worldspawn) {
+			lexer_perror(ls, "this entity is a worldspawn, but a "
+			                 "worldspawn was already read earlier");
+			goto error;
+		}
 
-	if (entity->classname && !strcmp(entity->classname, "worldspawn"))
-		merge_into_worldspawn(entity);
-	else
-		elist_append(&entities, entity, list);
+		map->worldspawn = entity;
+	} else
+		elist_append(&map->entities, entity, list);
 
 	return 0;
 error:
@@ -330,45 +299,15 @@ error:
 	return 1;
 }
 
+//
+// writing
+//
 
-int mapcat_load(const char *path)
-{
-	int rv = 1;
-	lexer_state_t lexer;
-	vstr_t token;
-
-	vstr_init(&token);
-
-	if (lexer_open(&lexer, path, &token)) {
-		perror(path);
-		return 1;
-	}
-
-	while (1) {
-		int ret;
-
-		ret = lexer_assert_or_eof(&lexer, "{",
-		                          "the beginning of an entity");
-		if (ret == -1)
-			break;
-		if (ret > 0)
-			goto out;
-
-		if (read_entity(&lexer))
-			goto out;
-	}
-
-	rv = 0;
-out:
-	vstr_free(&token);
-	return rv;
-}
-
-static int write_brush(FILE *fp, brush_t *brush)
+static int write_brush(FILE *fp, const brush_t *brush)
 {
-	brush_face_t *face;
+	const brush_face_t *face;
 
-	elist_for(face, brush->faces, list) {
+	elist_cfor(face, brush->faces, list) {
 		size_t i;
 
 		for (i = 0; i < 9; i += 3) {
@@ -397,18 +336,19 @@ static int write_brush(FILE *fp, brush_t *brush)
 	return 0;
 }
 
-static int write_entity(FILE *fp, entity_t *entity)
+static int write_entity(FILE *fp, const entity_t *entity)
 {
-	entity_key_t *key;
-	brush_t *brush;
+	const entity_key_t *key;
+	const brush_t *brush;
 	size_t brush_counter = 0;
 
-	fprintf(fp, "\"classname\" \"%s\"\n", entity->classname);
+	if (entity->classname)
+		fprintf(fp, "\"classname\" \"%s\"\n", entity->classname);
 
-	elist_for(key, entity->keys, list)
+	elist_cfor(key, entity->keys, list)
 		fprintf(fp, "\"%s\" \"%s\"\n", key->key, key->value);
 
-	elist_for(brush, entity->brushes, list) {
+	elist_cfor(brush, entity->brushes, list) {
 		fprintf(fp, "// brush %zu\n{\n", brush_counter);
 		write_brush(fp, brush);
 		fprintf(fp, "}\n");
@@ -421,11 +361,70 @@ static int write_entity(FILE *fp, entity_t *entity)
 	return 0;
 }
 
-int mapcat_save(const char *path)
+//
+// entry points
+//
+
+void map_init(map_t *map)
+{
+	memset(map, 0, sizeof(*map));
+}
+
+void map_free(map_t *map)
+{
+	entity_t *entity, *next;
+
+	if (map->worldspawn)
+		free_entity(map->worldspawn);
+
+	for (entity = map->entities; entity; entity = next) {
+		next = elist_next(entity, list);
+		free_entity(entity);
+	}
+}
+
+int map_read(map_t *map, const char *path)
+{
+	int rv = 1;
+	lexer_state_t lexer;
+	vstr_t token;
+
+	vstr_init(&token);
+
+	if (lexer_open(&lexer, path, &token)) {
+		perror(path);
+		return 1;
+	}
+
+	while (1) {
+		int ret;
+
+		ret = lexer_assert_or_eof(&lexer, "{",
+		                          "the beginning of an entity");
+		if (ret == -1)
+			break;
+		if (ret > 0)
+			goto out;
+
+		if (read_entity(&lexer, map))
+			goto out;
+	}
+
+	rv = 0;
+out:
+	vstr_free(&token);
+
+	if (rv)
+		map_free(map);
+
+	return rv;
+}
+
+int map_write(const map_t *map, const char *path)
 {
 	int rv = 1;
 	FILE *fp;
-	entity_t *entity;
+	const entity_t *entity;
 	size_t entity_counter = 1; // worldspawn is #0
 
 	fp = fopen(path, "w");
@@ -434,16 +433,16 @@ int mapcat_save(const char *path)
 		goto out;
 	}
 
-	if (!worldspawn) {
+	if (!map->worldspawn) {
 		fprintf(stderr, "error: worldspawn is missing\n");
 		goto out;
 	}
 
 	fprintf(fp, "// entity 0\n{\n");
-	write_entity(fp, worldspawn);
+	write_entity(fp, map->worldspawn);
 	fprintf(fp, "}\n");
 
-	elist_for(entity, entities, list) {
+	elist_cfor(entity, map->entities, list) {
 		fprintf(fp, "// entity %zu\n{\n", entity_counter);
 
 		if (write_entity(fp, entity)) {
@@ -469,15 +468,46 @@ out:
 	return rv;
 }
 
-void mapcat_free(void)
+//RETURN VALUE
+//	always 0 (this function cannot fail (yet))
+// slave is left in invalid state after this function returns, do not use it
+int map_merge(map_t *master, map_t *slave)
 {
-	entity_t *entity, *next;
+	if (!master->worldspawn) {
+		// the first worldspawn is kept intact
+		master->worldspawn = slave->worldspawn;
+	} else if (slave->worldspawn) {
+		// worldspawns of subsequent maps are discarded, except their
+		// brushes, which are appended to the master's worldspawn
+		elist_append_list(&master->worldspawn->brushes,
+		                  slave->worldspawn->brushes, list);
+
+		free_entity_keys(slave->worldspawn);
+		free(slave->worldspawn->classname);
+		free(slave->worldspawn);
+	}
 
-	if (worldspawn)
-		free_entity(worldspawn);
+	// entities are always kept intact
+	elist_append_list(&master->entities, slave->entities, list);
 
-	for (entity = entities; entity; entity = next) {
-		next = elist_next(entity, list);
-		free_entity(entity);
-	}
+	master->num_entities += slave->num_entities;
+	master->num_discarded_entities += slave->num_discarded_entities;
+	master->num_brushes += slave->num_brushes;
+	master->num_discarded_brushes += slave->num_discarded_brushes;
+
+	return 0;
+}
+
+void map_print_stats(const char *path, const map_t *map)
+{
+	size_t ents_with_worldspawn;
+
+	ents_with_worldspawn = map->num_entities + (map->worldspawn ? 1 : 0);
+
+	printf("%s: ", path);
+	printf("%zu entit%s (%zu discarded), %zu brush%s (%zu discarded)\n",
+	       ents_with_worldspawn, (ents_with_worldspawn == 1 ? "y" : "ies"),
+	       map->num_discarded_entities,
+	       map->num_brushes, (map->num_brushes == 1 ? "" : "es"),
+	       map->num_discarded_brushes);
 }
-- 
cgit