the backtrace file lines should be read at compile time, not runtime

Author: StavromulaBeta

src/cognac.c

@@ -82,17 +82,36 @@ static void* alloc(size_t n)
 	return (heap += n) - n;
 }
 
+char* escape_cstring(char* str)
+{
+	size_t len = strlen(str);
+	char* str2 = alloc(len*2 + 1);
+	int ii = 0;
+	for (int i = 0 ; i < len ; ++i)
+	{
+		switch (str[i])
+		{
+			case '\\': case '"':
+				str2[ii++] = '\\';
+			default:
+				str2[ii++] = str[i];
+				break;
+		}
+	}
+	return str2;
+}
+
 where_t* parse_pos(char* sym)
 {
 	where_t* p = alloc(sizeof *p);
 	p->mod = pmod;
 	p->line = yylloc.first_line;
 	p->col = yylloc.first_column;
+	p->line_str = pmod->lines[p->line-1];
 	p->symbol = sym;
 	return p;
 }
 
-
 _Noreturn void type_error(val_type_t expected, val_type_t got, where_t* pos)
 {
 	char buf[100];
@@ -410,21 +429,33 @@ module_t* create_module(char* path)
 
 void module_parse(module_t* mod)
 {
-	if (mod->path)
+	fseek(mod->file, 0, SEEK_SET);
+
+	mod->num_lines = 0;
+	while(!feof(mod->file)) if(fgetc(mod->file) == '\n') mod->num_lines++; // count lines.
+
+	mod->lines = alloc(sizeof(char*) * mod->num_lines);
+
+	fseek(mod->file, 0, SEEK_SET);
+
+	for (int i = 0 ; i < mod->num_lines ; ++i) // populate lines[]
 	{
-		FILE* t = fopen(mod->path, "r");
-		if (!t)
+		mod->lines[i] = (char*)alloc(1024);
+
+		for (int ii = 0 ; ii < 1023 ; ++ii)
 		{
-			if (!mod->first_ref)
-				fprintf(stderr, "\nCan't open file '%s'!\n", mod->path);
-			else
+			char c = fgetc(mod->file);
+			if (c == '\n')
 			{
-				throw_error("can't find module", mod->first_ref);
+				mod->lines[i][ii] = '\0';
+				break;
 			}
-			exit(EXIT_FAILURE);
+			else mod->lines[i][ii] = c;
 		}
-		fclose(t);
+		mod->lines[i][1023] = '\0';
 	}
+
+	fseek(mod->file, 0, SEEK_SET);
 	pmod = mod;
 	yyin = mod->file; // imagine having a reentrant parser.
 	yylloc.first_line = 1;
@@ -1067,7 +1098,7 @@ void to_c(module_t* mod)
 					}
 				case backtrace_push:
 					if (op->op->where && op->op->where->mod->path && op->op->where->symbol)
-						fprintf(c_source, "\tBACKTRACE_PUSH(\"%s\", %zu, %zu, \"%s\", %zu);\n", op->op->where->symbol, op->op->where->line, op->op->where->col, op->op->where->mod->path, bid++);
+						fprintf(c_source, "\tBACKTRACE_PUSH(\"%s\", %zu, %zu, \"%s\", \"%s\", %zu);\n", op->op->where->symbol, op->op->where->line, op->op->where->col, escape_cstring(op->op->where->mod->path), escape_cstring(op->op->where->line_str), bid++);
 					break;
 				case backtrace_pop:
 					if (op->op->where && op->op->where->mod->path && op->op->where->symbol)

src/cognac.h

@@ -224,6 +224,8 @@ struct _module_t
 	symbol_list_t* symbols;
 	module_list_t* uses;
 	where_t* first_ref;
+	size_t num_lines;
+	char** lines;
 };
 
 struct _module_list_t
@@ -238,6 +240,7 @@ struct _where_t
 	size_t line;
 	size_t col;
 	char* symbol;
+	char* line_str;
 };
 
 struct _where_list_t

src/runtime.h

@@ -131,6 +131,7 @@ typedef struct backtrace
 	const size_t line;
 	const size_t col;
 	const char* file;
+	const char* line_str;
 } backtrace;
 
 typedef struct var_info
@@ -384,38 +385,8 @@ static void cleanup(void)
 
 #ifdef DEBUG
 
-static char* get_source_line(size_t line, const char* source_file)
-{
-	// TODO maybe compile the line into the executable instead of rereading the source.
-	FILE* f = fopen(source_file, "r");
-	if (!f) return NULL;
-
-	for (;;)
-	{
-		if (line == 1) break;
-		if (fgetc(f) == '\n') line--;
-	}
-
-	char* buf = gc_malloc(1024);
-
-	int i = 0;
-
-	for (;; ++i)
-	{
-		char c = fgetc(f);
-		if (i == 1024 || c == '\n') break;
-		buf[i] = c;
-	}
-
-	buf[i] = '\0';
-
-	fclose(f);
-
-	return buf;
-}
-
-#define BACKTRACE_PUSH(NAME, LINE, COL, FILE, ID) \
-	const backtrace _trace_##LINE##_##COL##_##ID = (backtrace) {.name = NAME, .line = (LINE), .col = (COL), .file = (FILE), .next=trace}; \
+#define BACKTRACE_PUSH(NAME, LINE, COL, FILE, LINE_STR, ID) \
+	const backtrace _trace_##LINE##_##COL##_##ID = (backtrace) {.name = NAME, .line = (LINE), .col = (COL), .file = (FILE), .line_str=(LINE_STR), .next=trace}; \
 	trace = &_trace_##LINE##_##COL##_##ID;
 
 #define BACKTRACE_POP() \
@@ -569,15 +540,16 @@ static void print_backtrace(int n, const backtrace* b, int last_spaces)
 {
 	if (!b || !n) return;
 	int len = strlen(b->name);
-	char* ln = get_source_line(b->line, b->file);
-	if (!ln) fprintf("(can't open source file '%s' to create backtrace)\n", b->file);
+	const char* ln = b->line_str;
 	ssize_t col = b->col;
 	while (*ln)
 	{
 		if (*ln != ' ' && *ln != '\t') break;
 		ln++;
 		col--;
 	}
+	char* tabs;
+	for  (char* tabs ; *tabs ; tabs++) if (*tabs == '\t') *tabs = ' ';
 	char pos[128];
 	sprintf(pos, "[%s %zi:%zi]", b->file, b->line, b->col);
 	int spaces = (strlen(pos)) + col - len/2 - 1;