parsers: give parsers a set amount of space for state

..and don't try to cram all parser states into the
same struct.

3 files changed, 82 insertions, 56 deletions

diff --git a/include/lem-parsers.h b/include/lem-parsers.h
index b65becd..52ab696 100644
--- a/include/lem-parsers.h
+++ b/include/lem-parsers.h
@@ -21,23 +21,16 @@
 
 #include <lem.h>
 
+#define LEM_INPUTBUF_PSIZE (4*sizeof(size_t))
 #define LEM_INPUTBUF_SIZE 4096
 
 struct lem_inputbuf {
 	unsigned int start;
 	unsigned int end;
-	union {
-		void *p;
-		unsigned long u;
-	};
-	int parts;
+	char pstate[LEM_INPUTBUF_PSIZE];
 	char buf[LEM_INPUTBUF_SIZE];
 };
 
-enum lem_presult {
-	LEM_PMORE = 0,
-};
-
 enum lem_preason {
 	LEM_PCLOSED,
 	LEM_PERROR,
diff --git a/lem/http/core.c b/lem/http/core.c
index 9fdd954..2186294 100644
--- a/lem/http/core.c
+++ b/lem/http/core.c
@@ -153,6 +153,11 @@ static const unsigned char state_table[SMAX][C_MAX] = {
 /* SEND*/ { X___,XEND,X___,X___,X___,X___,X___,X___,X___,X___,X___,X___,X___ },
 };
 
+struct parse_http_state {
+	unsigned int w;
+	unsigned char state;
+};
+
 static void
 parse_http_init(lua_State *T)
 {
@@ -164,26 +169,32 @@ parse_http_init(lua_State *T)
 static void
 parse_http_req_init(lua_State *T, struct lem_inputbuf *b)
 {
-	b->u = S_GO;
+	struct parse_http_state *s = (struct parse_http_state *)&b->pstate;
+
+	s->w = 0;
+	s->state = S_GO;
 	parse_http_init(T);
 }
 
 static void
 parse_http_res_init(lua_State *T, struct lem_inputbuf *b)
 {
-	b->u = C_GO;
+	struct parse_http_state *s = (struct parse_http_state *)&b->pstate;
+
+	s->w = 0;
+	s->state = C_GO;
 	parse_http_init(T);
 }
 
 static int
 parse_http_process(lua_State *T, struct lem_inputbuf *b)
 {
-	unsigned char state = b->u & 0xFF;
-	unsigned int w = b->u >> 8;
+	struct parse_http_state *s = (struct parse_http_state *)&b->pstate;
+	unsigned int w = s->w;
 	unsigned int r = b->start;
-	unsigned int end = b->end;
+	unsigned char state = s->state;
 
-	while (r < end) {
+	while (r < b->end) {
 		unsigned char ch = b->buf[r++];
 
 		state = state_table[state][ch > 127 ? C_ETC : ascii_class[ch]];
@@ -296,7 +307,7 @@ parse_http_process(lua_State *T, struct lem_inputbuf *b)
 			}
 			lua_setfield(T, -2, "headers");
 
-			if (r == end)
+			if (r == b->end)
 				b->start = b->end = 0;
 			else
 				b->start = r;
@@ -313,8 +324,9 @@ parse_http_process(lua_State *T, struct lem_inputbuf *b)
 	}
 
 	b->start = b->end = w + 1;
-	b->u = (w << 8) | state;
-	return LEM_PMORE;
+	s->w = w;
+	s->state = state;
+	return 0;
 }
 
 static const struct lem_parser http_req_parser = {
diff --git a/lem/parsers/core.c b/lem/parsers/core.c
index 0b0bb10..affde27 100644
--- a/lem/parsers/core.c
+++ b/lem/parsers/core.c
@@ -24,10 +24,10 @@
 static int
 parse_available_process(lua_State *T, struct lem_inputbuf *b)
 {
-	size_t size = b->end - b->start;
+	unsigned int size = b->end - b->start;
 
 	if (size == 0)
-		return LEM_PMORE;
+		return 0;
 
 	lua_pushlstring(T, b->buf + b->start, size);
 	b->start = b->end = 0;
@@ -41,24 +41,31 @@ static const struct lem_parser parser_available = {
 /*
  * read a specified number of bytes
  */
+struct parse_target_state {
+	size_t target;
+	int parts;
+};
+
 static void
 parse_target_init(lua_State *T, struct lem_inputbuf *b)
 {
-	b->u = luaL_checknumber(T, 3);
-	b->parts = 0;
+	struct parse_target_state *s = (struct parse_target_state *)&b->pstate;
+
+	s->target = luaL_checknumber(T, 3);
+	s->parts = 0;
 	lua_settop(T, 2);
 }
 
 static int
 parse_target_process(lua_State *T, struct lem_inputbuf *b)
 {
-	unsigned long target = b->u;
-	unsigned int size = b->end - b->start;
+	struct parse_target_state *s = (struct parse_target_state *)&b->pstate;
+	size_t size = b->end - b->start;
 
-	if ((unsigned long)size >= target) {
-		lua_pushlstring(T, b->buf + b->start, target);
-		lua_concat(T, b->parts + 1);
-		b->start += target;
+	if (size >= s->target) {
+		lua_pushlstring(T, b->buf + b->start, s->target);
+		lua_concat(T, s->parts + 1);
+		b->start += s->target;
 		if (b->start == b->end)
 			b->start = b->end = 0;
 
@@ -67,16 +74,16 @@ parse_target_process(lua_State *T, struct lem_inputbuf *b)
 
 	if (b->end == LEM_INPUTBUF_SIZE) {
 		lua_pushlstring(T, b->buf + b->start, size);
-		b->parts++;
-		if (b->parts == LUA_MINSTACK-2) {
+		s->parts++;
+		if (s->parts == LUA_MINSTACK-2) {
 			lua_concat(T, LUA_MINSTACK-2);
-			b->parts = 1;
+			s->parts = 1;
 		}
 		b->start = b->end = 0;
-		b->u = target - size;
+		s->target -= size;
 	}
 
-	return LEM_PMORE;
+	return 0;
 }
 
 static const struct lem_parser parser_target = {
@@ -87,46 +94,55 @@ static const struct lem_parser parser_target = {
 /*
  * read all data until stream closes
  */
+struct parse_all_state {
+	int parts;
+};
+
 static void
 parse_all_init(lua_State *T, struct lem_inputbuf *b)
 {
-	b->parts = 0;
+	struct parse_all_state *s = (struct parse_all_state *)&b->pstate;
+
+	s->parts = 0;
 	lua_settop(T, 2);
 }
 
 static int
 parse_all_process(lua_State *T, struct lem_inputbuf *b)
 {
+	struct parse_all_state *s = (struct parse_all_state *)&b->pstate;
+
 	if (b->end == LEM_INPUTBUF_SIZE) {
 		lua_pushlstring(T, b->buf + b->start,
 				LEM_INPUTBUF_SIZE - b->start);
-		b->parts++;
-		if (b->parts == LUA_MINSTACK-2) {
+		s->parts++;
+		if (s->parts == LUA_MINSTACK-2) {
 			lua_concat(T, LUA_MINSTACK-2);
-			b->parts = 1;
+			s->parts = 1;
 		}
 		b->start = b->end = 0;
 	}
 
-	return LEM_PMORE;
+	return 0;
 }
 
 static int
 parse_all_destroy(lua_State *T, struct lem_inputbuf *b, enum lem_preason reason)
 {
+	struct parse_all_state *s = (struct parse_all_state *)&b->pstate;
 	unsigned int size;
 
 	if (reason != LEM_PCLOSED)
-		return LEM_PMORE;
+		return 0;
 
 	size = b->end - b->start;
 	if (size > 0) {
 		lua_pushlstring(T, b->buf + b->start, size);
-		b->parts++;
-		b->start = b->end = 0;
+		s->parts++;
 	}
+	b->start = b->end = 0;
 
-	lua_concat(T, b->parts);
+	lua_concat(T, s->parts);
 	return 1;
 }
 
@@ -139,26 +155,32 @@ static const struct lem_parser parser_all = {
 /*
  * read a line
  */
+struct parse_line_state {
+	int parts;
+	char stopbyte;
+};
+
 static void
 parse_line_init(lua_State *T, struct lem_inputbuf *b)
 {
+	struct parse_line_state *s = (struct parse_line_state *)&b->pstate;
 	const char *stopbyte = luaL_optstring(T, 3, "\n");
 
-	b->u = (b->start << 8) | stopbyte[0];
-	b->parts = 0;
+	s->parts = 0;
+	s->stopbyte = stopbyte[0];
 	lua_settop(T, 2);
 }
 
 static int
 parse_line_process(lua_State *T, struct lem_inputbuf *b)
 {
+	struct parse_line_state *s = (struct parse_line_state *)&b->pstate;
 	unsigned int i;
-	unsigned char stopbyte = b->u & 0xFF;
 
-	for (i = b->u >> 8; i < b->end; i++) {
-		if (b->buf[i] == stopbyte) {
+	for (i = b->start; i < b->end; i++) {
+		if (b->buf[i] == s->stopbyte) {
 			lua_pushlstring(T, b->buf + b->start, i - b->start);
-			lua_concat(T, b->parts + 1);
+			lua_concat(T, s->parts + 1);
 			i++;
 			if (i == b->end)
 				b->start = b->end = 0;
@@ -169,18 +191,17 @@ parse_line_process(lua_State *T, struct lem_inputbuf *b)
 	}
 
 	if (b->end == LEM_INPUTBUF_SIZE) {
-		lua_pushlstring(T, b->buf + b->start, b->end - b->start);
-		b->parts++;
-		if (b->parts == LUA_MINSTACK-2) {
+		lua_pushlstring(T, b->buf + b->start,
+				LEM_INPUTBUF_SIZE - b->start);
+		s->parts++;
+		if (s->parts == LUA_MINSTACK-2) {
 			lua_concat(T, LUA_MINSTACK-2);
-			b->parts = 1;
+			s->parts = 1;
 		}
 		b->start = b->end = 0;
-		b->u = stopbyte;
-	} else
-		b->u = (i << 8) | stopbyte;
+	}
 
-	return LEM_PMORE;
+	return 0;
 }
 
 static const struct lem_parser parser_line = {