Added break statement to templates

Added a break statement that can break out of loops, also added
some tests to test the functionality of the same.

1 files changed, 191 insertions, 0 deletions

diff --git a/src/lexer.c b/src/lexer.c
new file mode 100644
index 0000000..13f80b8
--- /dev/null
+++ b/src/lexer.c
@@ -0,0 +1,191 @@
+#include "lexer.h"
+
+struct TMPL_token*           TMPL_alloc_token(void);
+void                         TMPL_free_token(struct TMPL_token* token);
+enum TMPL_tagtype            starts_with_token(const char* str, size_t strlen);
+size_t                       tagtype_len(enum TMPL_tagtype t);
+struct TMPL_token*           scan_text(
+                                       const char* start,
+                                       size_t strlen,
+                                       size_t* consumed
+                                      );
+struct TMPL_token*           scan_tag(
+                                      const char* start,
+                                      size_t strlen,
+                                      size_t* consumed
+                                     );
+void                         print_tokens(struct TMPL_token* head);
+
+
+/*Allocates a token*/
+struct TMPL_token*
+TMPL_alloc_token(){
+	struct TMPL_token* ret = (struct TMPL_token*)malloc(sizeof(struct TMPL_token));
+	ret->next = NULL;
+	return ret;
+}
+
+/*Frees an allocated token*/
+void
+TMPL_free_token(struct TMPL_token* token){
+	struct TMPL_token* cursor = token;
+	while(cursor != NULL){
+		struct TMPL_token* this = cursor;
+		cursor = cursor->next;
+		free(this);
+	}
+}
+
+/*Check if it starts with the names of any of our tokens*/
+enum TMPL_tagtype
+starts_with_token(const char* str, size_t strlen){
+	/*Make sure we get TMPL_ first*/
+	if(strlen < 5){
+		return tag_null;
+	}
+	if(*str != 'T'
+	|| *(str + 1) != 'M'
+	|| *(str + 2) != 'P'
+	|| *(str + 3) != 'L'
+	|| *(str + 4) != '_'){
+		return tag_null;
+	}
+	if(strlen > TAG_VAR_LENGTH
+	&& *(str + 5) == 'V'
+	&& *(str + 6) == 'A'
+	&& *(str + 7) == 'R'
+	&& *(str + 8) == ' '){
+		return tag_var;
+	}else if(strlen > TAG_IF_LENGTH
+	&& *(str + 5) == 'I'
+	&& *(str + 6) == 'F'
+	&& *(str + 7) == ' '){
+		return tag_if;
+	}else if(strlen > TAG_END_LENGTH
+	&& *(str + 5) == 'E'
+	&& *(str + 6) == 'N'
+	&& *(str + 7) == 'D'){
+		return tag_end;
+	}else if(strlen > TAG_ELSE_LENGTH
+	&& *(str + 5) == 'E'/*Check for both else and elseif*/
+	&& *(str + 6) == 'L'
+	&& *(str + 7) == 'S'
+	&& *(str + 8) == 'E'){
+		if(*(str + 9) != 'I'){
+			return tag_else;
+		}else if(strlen > TAG_ELSEIF_LENGTH
+		&& *(str + 9) == 'I'
+		&& *(str + 10) == 'F'
+		&& *(str + 11) == ' '){
+			return tag_elseif;
+		}else{
+			return tag_null;
+		}
+	}else if(strlen > TAG_LOOP_LENGTH
+	&& *(str + 5) == 'L'
+	&& *(str + 6) == 'O'
+	&& *(str + 7) == 'O'
+	&& *(str + 8) == 'P'
+	&& *(str + 9) == ' '){
+		return tag_loop;
+	}else if(strlen > TAG_BREAK_LENGTH
+	&& *(str + 5) == 'B'
+	&& *(str + 6) == 'R'
+	&& *(str + 7) == 'E'
+	&& *(str + 8) == 'A'
+	&& *(str + 9) == 'K'){
+		return tag_break;
+	}else if(strlen > TAG_CONTINUE_LENGTH
+	&& *(str + 5) == 'C'
+	&& *(str + 6) == 'O'
+	&& *(str + 7) == 'N'
+	&& *(str + 8) == 'T'
+	&& *(str + 9) == 'I'
+	&& *(str + 10) == 'N'
+	&& *(str + 11) == 'U'
+	&& *(str + 12) == 'E'){
+		return tag_continue;
+	}else{
+		return tag_null;
+	}
+}
+
+/*Find the lenth of a tag*/
+size_t
+tagtype_len(enum TMPL_tagtype t){
+	switch(t){
+		case tag_null:
+			return TAG_NULL_LENGTH;
+		case tag_text:
+			return TAG_TEXT_LENGTH;
+		case tag_var:
+			return TAG_VAR_LENGTH;
+		case tag_if:
+			return TAG_IF_LENGTH;
+		case tag_end:
+			return TAG_END_LENGTH;
+		case tag_elseif:
+			return TAG_ELSEIF_LENGTH;
+		case tag_else:
+			return TAG_ELSE_LENGTH;
+		case tag_loop:
+			return TAG_LOOP_LENGTH;
+		case tag_break:
+			return TAG_BREAK_LENGTH;
+		case tag_continue:
+			return TAG_CONTINUE_LENGTH;
+	}
+	return 0;
+}
+
+/*Quickly find the token*/
+struct TMPL_token*
+scan_text(const char* start, size_t strlen, size_t* consumed){
+	struct TMPL_token* t = TMPL_alloc_token();
+	t->start = start;
+	enum TMPL_tagtype type = tag_null;
+	const char* cursor = start;
+	while(type == tag_null){
+		int left = strlen - (cursor - start);
+		cursor = (const char*)memchr(cursor,'<',left);
+		if(cursor == NULL){
+			cursor = start + (strlen > 0 ? strlen : 1);
+			break;
+		}
+		type = starts_with_token(cursor+1,strlen);
+		if(type == tag_null){
+			cursor++;
+		}
+	}
+	t->end = cursor;
+	t->length = t->end - t->start;
+	*consumed = t->length;
+	return t;
+}
+
+struct TMPL_token*
+scan_tag(const char* start, size_t strlen, size_t* consumed){
+	struct TMPL_token* t = TMPL_alloc_token();
+	t->start = start;
+	char* cursor = (char*)memchr(start,'>',strlen);
+	t->end = cursor+1;/*Include the '>'*/
+	t->length = t->end - t->start;
+	*consumed = t->length;
+	return t;
+}
+
+void
+print_tokens(struct TMPL_token* head){
+	struct TMPL_token* cursor = head;
+	while(cursor != NULL){
+		printf("char start is %p char end is %p cursor is %p type is %d\n",cursor->start, cursor->end,(void*)cursor,(int)cursor->type);
+		const char* i;
+		for(i = cursor->start; i != cursor->end; i++){
+			printf("%c",*i);
+		}
+		printf("\n----\n");
+		cursor = cursor->next;
+	}
+	printf("Finished printing tokens\n");
+}
+