Better error logging

10 files changed, 116 insertions, 113 deletions

diff --git a/inc/context.h b/inc/context.h
index b11e23d..5b314d7 100644
--- a/inc/context.h
+++ b/inc/context.h
@@ -2,18 +2,25 @@
 #define CONTEXT_H
 
 #include <stddef.h>
+#include <stdio.h>
 
 typedef struct {
 	size_t start, end;
 } ctx_string;
 
-struct ctx {
+struct ctx_location {
 	size_t line;
 	size_t column;
 	const char *path;
 
-	char *raw;
-	char *data;
+	char *data; // Raw
+	size_t size;
+};
+
+struct ctx {
+	struct ctx_location location;
+
+	char *data; // Preprocessed
 	size_t size;
 
 	size_t token_count;
@@ -27,6 +34,7 @@ struct ctx {
 
 struct ctx *context_create(const char *path);
 void context_destroy(struct ctx *ctx);
+void context_print(FILE *fd, struct ctx_location *location);
 void context_rewind(struct ctx *ctx);
 
 #endif
diff --git a/inc/log.h b/inc/log.h
index 4698f9c..da82233 100644
--- a/inc/log.h
+++ b/inc/log.h
@@ -3,7 +3,6 @@
 
 #include <context.h>
 
-__attribute__((noreturn)) void errln(struct ctx *ctx, const char *fmt, ...);
-__attribute__((noreturn)) void err(const char *fmt, ...);
+__attribute__((noreturn)) void errln(struct ctx_location *location, const char *fmt, ...);
 
 #endif
diff --git a/inc/tokenize.h b/inc/tokenize.h
index d1a2931..f5e8600 100644
--- a/inc/tokenize.h
+++ b/inc/tokenize.h
@@ -28,6 +28,7 @@ enum token_type {
 
 struct token {
 	enum token_type type;
+	struct ctx_location location;
 	ctx_string string;
 };
 
diff --git a/src/context.c b/src/context.c
index ff0291a..be93db0 100644
--- a/src/context.c
+++ b/src/context.c
@@ -1,6 +1,7 @@
 #include <assert.h>
-#include <stdio.h>
+#include <math.h>
 #include <stdlib.h>
+#include <string.h>
 
 #include <context.h>
 #include <tokenize.h>
@@ -10,23 +11,23 @@ struct ctx *context_create(const char *path)
 {
 	struct ctx *ctx = calloc(1, sizeof(*ctx));
 	ctx->tokens = calloc(TOKENS_MAX, sizeof(*ctx->tokens));
-	ctx->path = path; // TODO: strdup?
+	ctx->location.path = path; // TODO: strdup?
 
 	FILE *file = fopen(path, "r");
 	assert(file);
 
 	// Find size of file
 	fseek(file, 0, SEEK_END);
-	ctx->size = ftell(file);
+	ctx->location.size = ftell(file);
 	rewind(file);
-	assert(ctx->size);
+	assert(ctx->location.size);
 
-	ctx->raw = malloc(ctx->size + 1);
-	assert(ctx->raw);
-	fread(ctx->raw, 1, ctx->size, file);
+	ctx->location.data = malloc(ctx->location.size + 1);
+	assert(ctx->location.data);
+	fread(ctx->location.data, 1, ctx->location.size, file);
 	fclose(file);
 
-	ctx->raw[ctx->size] = 0;
+	ctx->location.data[ctx->location.size] = 0;
 
 	ctx->tree.head = tree_create();
 	ctx->tree.current = NULL;
@@ -39,10 +40,10 @@ void context_destroy(struct ctx *ctx)
 	if (!ctx)
 		return;
 
-	if (ctx->raw)
-		free(ctx->raw);
+	if (ctx->location.data)
+		free(ctx->location.data);
 
-	if (ctx->data && ctx->data != ctx->raw)
+	if (ctx->data && ctx->data != ctx->location.data)
 		free(ctx->data);
 
 	if (ctx->tokens)
@@ -54,8 +55,47 @@ void context_destroy(struct ctx *ctx)
 	free(ctx);
 }
 
+#define CONTEXT_COUNT 3
+void context_print(FILE *fd, struct ctx_location *location)
+{
+	size_t start_line = fmax((int)location->line - CONTEXT_COUNT, 0);
+	size_t end_line = location->line + CONTEXT_COUNT + 1;
+
+	for (size_t line = 0, index = 0; line < end_line;) {
+		if (line < start_line) {
+			if (location->data[index++] == '\n')
+				line++;
+			continue;
+		}
+
+		const char *end = strchr(location->data + index, '\n') + 1;
+		assert(end);
+		size_t length = end - (location->data + index) - 1;
+
+		if (location->line == line) {
+			int pointer_length = location->column + 9;
+			char *pointer = malloc(pointer_length); // Literally a pointer
+			fprintf(fd,
+				"\x1B[1;32m%6lu | %.*s\x1B[1;31m%c\x1B[1;32m%.*s\n\x1B[1;31m%.*s%c\x1B[0m\n",
+				line + 1, (int)location->column, location->data + index,
+				*(location->data + index + location->column),
+				(int)(length - location->column - 1),
+				location->data + index + location->column + 1, pointer_length,
+				(char *)memset(pointer, '~', pointer_length), '^');
+			free(pointer);
+		} else {
+			fprintf(fd, "%6lu | %.*s\n", line + 1, (int)length, location->data + index);
+		}
+
+		index = end - location->data;
+		line++;
+		if (index >= location->size)
+			return;
+	}
+}
+
 void context_rewind(struct ctx *ctx)
 {
-	ctx->line = 0;
-	ctx->column = 0;
+	ctx->location.line = 0;
+	ctx->location.column = 0;
 }
diff --git a/src/lint.c b/src/lint.c
index 5ff1864..7c2e9da 100644
--- a/src/lint.c
+++ b/src/lint.c
@@ -17,5 +17,5 @@ void lint(struct ctx *ctx)
 	}
 
 	if (parens != 0)
-		errln(ctx, "Invalid parens balance");
+		errln(&ctx->location, "Invalid parens balance");
 }
diff --git a/src/log.c b/src/log.c
index 5820a67..0e59ea2 100644
--- a/src/log.c
+++ b/src/log.c
@@ -1,78 +1,24 @@
+#include <assert.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 
 #include <log.h>
 
-static void context_print(FILE *fd, struct ctx *ctx)
+void errln(struct ctx_location *location, const char *fmt, ...)
 {
-	const char *data = ctx->data ? ctx->data : ctx->raw;
+	fprintf(stderr, "\x1B[1;36m%s:%lu:%lu:\x1B[0m ", location->path, location->line + 1,
+		location->column + 1);
 
-	// Find line, column
-	size_t line = 0, column = 0, index = 0;
-	for (; index < ctx->size; index++) {
-		char cur = data[index];
+	fprintf(stderr, "\x1B[1;31mError:\x1B[0m ");
 
-		column++;
-
-		if (line == ctx->line && column == ctx->column)
-			break;
-
-		if (cur == '\n') {
-			line++;
-			column = 0;
-			continue;
-		} else if (cur == '\0') {
-			fprintf(stderr, "Invalid context!");
-			context_destroy(ctx);
-			exit(1);
-			break;
-		}
-	}
-
-	if (++index >= ctx->size)
-		return; // Couldn't find context, idc?
-
-	fprintf(fd, "\x1B[1;36m%s:%ld:%ld:\x1B[0m '", ctx->path, ctx->line + 1, ctx->column + 1);
-
-	// Print line context
-	size_t start = ctx->column > 5 ? index - 5 : index;
-	size_t end = ctx->size - index > 5 ? index + 5 : index + 1;
-	for (size_t i = start; i < end; i++) {
-		if (i == index) {
-			fprintf(fd, "\x1B[1;32m%c\x1B[0m", data[i]);
-		} else {
-			fprintf(fd, "%c", data[i]);
-		}
-	}
-	fprintf(fd, "': ");
-}
-
-void errln(struct ctx *ctx, const char *fmt, ...)
-{
-	context_print(stderr, ctx);
-
-	fprintf(stderr, "\x1B[1;31m");
 	va_list ap;
 	va_start(ap, fmt);
 	vfprintf(stderr, fmt, ap);
-	fprintf(stderr, "\n");
 	va_end(ap);
-	fprintf(stderr, "\x1B[0m");
 
-	context_destroy(ctx);
-	exit(1);
-}
-
-void err(const char *fmt, ...)
-{
-	fprintf(stderr, "\x1B[1;31m");
-	va_list ap;
-	va_start(ap, fmt);
-	vfprintf(stderr, fmt, ap);
 	fprintf(stderr, "\n");
-	va_end(ap);
-	fprintf(stderr, "\x1B[0m");
+	context_print(stderr, location);
 
 	exit(1);
 }
diff --git a/src/main.c b/src/main.c
index 0e6807d..5827913 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1,3 +1,6 @@
+#include <stdio.h>
+#include <stdlib.h>
+
 #include <context.h>
 #include <lint.h>
 #include <log.h>
@@ -7,8 +10,10 @@
 
 int main(int argc, char *argv[])
 {
-	if (argc < 2)
-		err("Not enough arguments!");
+	if (argc < 2) {
+		fprintf(stderr, "Not enough arguments!");
+		exit(1);
+	}
 
 	struct ctx *ctx = context_create(argv[1]);
 	preprocess(ctx);
diff --git a/src/preprocess.c b/src/preprocess.c
index 8d9394a..3a0c0bc 100644
--- a/src/preprocess.c
+++ b/src/preprocess.c
@@ -1,6 +1,7 @@
 #include <assert.h>
 #include <math.h>
 #include <stddef.h>
+#include <stdlib.h>
 #include <string.h>
 
 #include <log.h>
@@ -8,43 +9,46 @@
 
 static void preprocess_erase(struct ctx *ctx, size_t start)
 {
-	assert(ctx->raw[start] == '#');
+	assert(ctx->data[start] == '#');
 
 	for (size_t i = start; i < ctx->size; i++) {
-		char cur = ctx->raw[i];
+		char cur = ctx->data[i];
 		if (cur == '\n' || cur == '\0')
 			break;
 
-		ctx->raw[i] = ' '; // Spaces get skipped by tokenizer anyways
+		ctx->data[i] = ' '; // Spaces get skipped by tokenizer anyways
 	}
 }
 
 void preprocess(struct ctx *ctx)
 {
-	for (size_t i = 0; i < ctx->size; i++) {
-		const char cur = ctx->raw[i];
+	ctx->size = ctx->location.size;
+	ctx->data = malloc(ctx->size);
+	memcpy(ctx->data, ctx->location.data, ctx->size);
 
-		ctx->column++;
+	for (size_t i = 0; i < ctx->location.size; i++) {
+		const char cur = ctx->location.data[i];
+
+		ctx->location.column++;
 
 		if (cur == '\n') {
-			ctx->line++;
-			ctx->column = 0;
+			ctx->location.line++;
+			ctx->location.column = 0;
 			continue;
 		} else if (cur == '\0') {
 			break;
-		} else if (cur == '#' && ctx->column == 1) {
-			if (strncmp(ctx->raw + i + 1, "inc ", fmin(4, ctx->size - i)) == 0) {
+		} else if (cur == '#' && ctx->location.column == 1) {
+			if (strncmp(ctx->location.data + i + 1, "inc ",
+				    fmin(4, ctx->location.size - i)) == 0) {
 				// TODO: Add include features
-			} else if (*(ctx->raw + i + 1) == '#') {
+			} else if (*(ctx->location.data + i + 1) == '#') {
 				// Comment
 			} else {
-				errln(ctx, "Invalid preprocessing directive");
+				errln(&ctx->location, "Invalid preprocessing directive");
 			}
 			preprocess_erase(ctx, i);
 		}
 	}
 
-	ctx->data = ctx->raw;
-	ctx->line = 0;
-	ctx->column = 0;
+	context_rewind(ctx);
 }
diff --git a/src/tokenize.c b/src/tokenize.c
index 02059a8..2a0eea6 100644
--- a/src/tokenize.c
+++ b/src/tokenize.c
@@ -13,7 +13,7 @@ static char next_non_alnum(struct ctx *ctx, size_t start)
 		if (!isalnum(ctx->data[i]))
 			return ctx->data[i];
 
-	errln(ctx, "Unexpected end of buffer");
+	errln(&ctx->location, "Unexpected end of buffer");
 }
 
 static bool peek_to_is_alnum(struct ctx *ctx, size_t start, char ch)
@@ -28,7 +28,7 @@ static bool peek_to_is_alnum(struct ctx *ctx, size_t start, char ch)
 			return false;
 	}
 
-	errln(ctx, "Unexpected end of buffer");
+	errln(&ctx->location, "Unexpected end of buffer");
 }
 
 static size_t peek_alnum_to(struct ctx *ctx, size_t start, char ch)
@@ -40,10 +40,10 @@ static size_t peek_alnum_to(struct ctx *ctx, size_t start, char ch)
 			return i;
 
 		if (!isalnum(cur))
-			errln(ctx, "'%c' is not alpha-numeric", cur);
+			errln(&ctx->location, "'%c' is not alpha-numeric", cur);
 	}
 
-	errln(ctx, "Unexpected end of buffer");
+	errln(&ctx->location, "Unexpected end of buffer");
 }
 
 static size_t peek_identifier(struct ctx *ctx, size_t start, char ch)
@@ -55,10 +55,10 @@ static size_t peek_identifier(struct ctx *ctx, size_t start, char ch)
 			return i;
 
 		if (!isalnum(cur) && (cur < '!' || cur > '~'))
-			errln(ctx, "'%c' is not an identifier", cur);
+			errln(&ctx->location, "'%c' is not an identifier", cur);
 	}
 
-	errln(ctx, "Unexpected end of buffer");
+	errln(&ctx->location, "Unexpected end of buffer");
 }
 
 static size_t peek_to(struct ctx *ctx, size_t start, char ch)
@@ -70,7 +70,7 @@ static size_t peek_to(struct ctx *ctx, size_t start, char ch)
 			return i;
 	}
 
-	errln(ctx, "Unexpected end of buffer");
+	errln(&ctx->location, "Unexpected end of buffer");
 }
 
 static void token_add(struct ctx *ctx, enum token_type type, size_t start, size_t end)
@@ -79,15 +79,16 @@ static void token_add(struct ctx *ctx, enum token_type type, size_t start, size_
 	token.type = type;
 	token.string.start = start;
 	token.string.end = end;
+	token.location = ctx->location;
 
 	assert(++ctx->token_count < TOKENS_MAX);
 	ctx->tokens[ctx->token_count] = token;
 
 	if (type == NEWLINE) {
-		ctx->line++;
-		ctx->column = 0;
+		ctx->location.line++;
+		ctx->location.column = 0;
 	} else {
-		ctx->column += end - start;
+		ctx->location.column += end - start;
 	}
 }
 
@@ -95,15 +96,14 @@ void token_print(struct ctx *ctx, struct token *token)
 {
 	assert(token->type != UNKNOWN);
 
-	printf("[token type=%d] '", token->type);
+	printf("[token type=%d] ", token->type);
 	if (token->type == NEWLINE || token->type == END) {
 		printf("' (Unprintable)\n");
 		return;
 	}
 
-	for (size_t i = token->string.start; i < token->string.end; i++)
-		printf("%c", ctx->data[i]);
-	printf("'\n");
+	printf("'%.*s'\n", (int)(token->string.end - token->string.start),
+	       ctx->data + token->string.start);
 }
 
 void tokenize(struct ctx *ctx)
@@ -131,7 +131,7 @@ void tokenize(struct ctx *ctx)
 			token_add(ctx, EQUAL, i, i + 1);
 			continue;
 		case ' ':
-			ctx->column++;
+			ctx->location.column++;
 			continue;
 		default:
 			break;
@@ -145,7 +145,7 @@ void tokenize(struct ctx *ctx)
 			} else { // Unnamed identifier ('_')
 				end_param = peek_to(ctx, start_param, ' ');
 				if (end_param - start_param != 1 || ctx->data[start_param] != '_')
-					errln(ctx, "Invalid param identifier");
+					errln(&ctx->location, "Invalid param identifier");
 			}
 
 			token_add(ctx, TYPE, i, start_param - 1);
diff --git a/src/treeify.c b/src/treeify.c
index 8da6481..5539d21 100644
--- a/src/treeify.c
+++ b/src/treeify.c
@@ -12,7 +12,7 @@ static void __expect(struct ctx *ctx, struct token *token, enum token_type type,
 	if (token->type != type) {
 		printf("[DBG] %s:%d: %s\n", file, line, func);
 		token_print(ctx, token);
-		err("Expected token of type %s!\n", type_enum);
+		errln(&token->location, "Expected token of type %s", type_enum);
 	}
 }