sic

commit e39faa528865d7a5109c9631bbb33f13dc29cb49
parent 0cc603389b08252b018c330f35c9e16075ff7e17
Author: citbl <citbl@citbl.org>
Date:   Tue, 12 May 2026 20:29:39 +1000

fixes

Diffstat:
M
src/lexer.c
 | 
13
+++++++++----
M
src/str.c
 | 
13
++++++++++---
M
src/utils.c
 | 
18
++++++++++++++++--

3 files changed, 35 insertions(+), 9 deletions(-)
diff --git a/src/lexer.c b/src/lexer.c
@@ -3,14 +3,19 @@
 #include <ctype.h>
 
 #include "lexer.h"
-#include "str.h"
 
 static void add_token(Lexer* lex, Token t)
 {
+    size_t new_cap;
+    Token* p;
+
     if (lex->len >= lex->cap) {
-        lex->cap = lex->cap == 0 ? 256 : lex->cap * 2;
-        lex->tokens = realloc(lex->tokens, lex->cap * sizeof(Token));
-        check(lex->tokens == NULL, "could not allocate memory for the tokens\n");
+        new_cap = lex->cap == 0 ? 256 : lex->cap * 2;
+        check(new_cap <= lex->cap || new_cap > SIZE_MAX / sizeof(Token), "token capacity overflow\n");
+        p = realloc(lex->tokens, lex->cap * sizeof(Token));
+        check(!p, "token reallocation failed\n");
+        lex->tokens = p;
+        lex->cap = new_cap;
     }
 
     lex->tokens[lex->len++] = t;
diff --git a/src/str.c b/src/str.c
@@ -4,11 +4,18 @@
 
 void str_append(Str* str, const char c)
 {
+    size_t new_cap;
+    char* s;
+
     if (str->len >= str->cap) {
-        str->cap = str->cap == 0 ? 32 : str->cap * 2;
-        str->value = realloc(str->value, str->cap * sizeof(char));
-        check(str->value == NULL, "str_append: could not alloc string\n");
+        new_cap = str->cap == 0 ? 32 : str->cap * 2;
+        check(new_cap <= str->cap || new_cap > SIZE_MAX / sizeof(Str), "could not reallocate string\n");
+        s = realloc(str->value, new_cap * sizeof(char));
+        check(s == NULL, "str_append: could not alloc string\n");
+        str->cap = new_cap;
+        str->value = s;
     }
 
     str->value[str->len++] = c;
+    str->value[str->len] = '\0';  // important!
 }
diff --git a/src/utils.c b/src/utils.c
@@ -8,17 +8,31 @@ char* read_file(const char* filename)
 {
     long fsize;
     char* source;
-    FILE* fp = fopen(filename, "r");
+    FILE* fp = fopen(filename, "rb");
     if (fp == NULL) {
         fprintf(stderr, "file not found\n");
         return NULL;
     }
 
-    fseek(fp, 0, SEEK_END);
+    if (fseek(fp, 0, SEEK_END) != 0) {
+        fprintf(stderr, "could not read file\n");
+        fclose(fp);
+        exit(1);
+    }
+
     fsize = ftell(fp);
+    if (fsize < 0) {
+        fprintf(stderr, "could not read size of file to load\n");
+        fclose(fp);
+        exit(1);
+    }
     fseek(fp, 0, SEEK_SET);
 
     source = malloc(fsize + 1);
+    if (!source) {
+        fprintf(stderr, "could not allocate memory to read file\n");
+        exit(1);
+    }
     fread(source, fsize, 1, fp);
     fclose(fp);