1 files changed, 10 insertions, 93 deletions

diff --git a/src/wasm-parser-lexer-shared.c b/src/wasm-parser-lexer-shared.c
index 7cc10057..599f7c2b 100644
--- a/src/wasm-parser-lexer-shared.c
+++ b/src/wasm-parser-lexer-shared.c
@@ -49,107 +49,24 @@ void wasm_format_error(WasmSourceErrorHandler* error_handler,
 
   char* source_line = NULL;
   size_t source_line_length = 0;
-  size_t source_line_column_offset = 0;
+  int source_line_column_offset = 0;
   size_t source_line_max_length = error_handler->source_line_max_length;
   if (loc) {
     source_line = alloca(source_line_max_length + 1);
-
-    size_t line_offset = wasm_lexer_get_file_offset_from_line(lexer, loc->line);
-    FILE* lexer_file = wasm_lexer_get_file(lexer);
-    long old_offset = ftell(lexer_file);
-    if (old_offset != -1) {
-      size_t next_line_offset =
-          wasm_lexer_get_file_offset_from_line(lexer, loc->line + 1);
-      if (next_line_offset == WASM_INVALID_LINE_OFFSET) {
-        /* we haven't gotten to the next line yet. read the file to find it. - 1
-         because columns are 1-based */
-        size_t offset = line_offset + (loc->last_column - 1);
-        next_line_offset = offset;
-        if (fseek(lexer_file, offset, SEEK_SET) != -1) {
-          char buffer[256];
-          while (1) {
-            size_t bytes_read = fread(buffer, 1, sizeof(buffer), lexer_file);
-            if (bytes_read <= 0)
-              break;
-
-            char* newline = memchr(buffer, '\n', bytes_read);
-            if (newline) {
-              next_line_offset += (newline - buffer);
-              break;
-            } else {
-              next_line_offset += bytes_read;
-            }
-          }
-        }
-      } else {
-        /* don't include the newline */
-        next_line_offset--;
-      }
-
-      source_line_length = next_line_offset - line_offset;
-      size_t column_range = loc->last_column - loc->first_column;
-      size_t start_offset = line_offset;
-      if (source_line_length > source_line_max_length) {
-        source_line_length = source_line_max_length;
-        size_t center_on;
-        if (column_range > source_line_max_length) {
-          /* the column range doesn't fit, just center on first_column */
-          center_on = loc->first_column - 1;
-        } else {
-          /* the entire range fits, display it all in the center */
-          center_on = (loc->first_column + loc->last_column) / 2 - 1;
-        }
-        if (center_on > source_line_max_length / 2)
-          start_offset = line_offset + center_on - source_line_max_length / 2;
-        if (start_offset > next_line_offset - source_line_max_length)
-          start_offset = next_line_offset - source_line_max_length;
-      }
-
-      source_line_column_offset = start_offset - line_offset;
-
-      char* p = source_line;
-      size_t read_start = start_offset;
-      size_t read_length = source_line_length;
-      WasmBool has_start_ellipsis = start_offset != line_offset;
-      WasmBool has_end_ellipsis =
-          start_offset + source_line_length != next_line_offset;
-
-      if (has_start_ellipsis) {
-        memcpy(p, "...", 3);
-        p += 3;
-        read_start += 3;
-        read_length -= 3;
-      }
-
-      if (has_end_ellipsis) {
-        read_length -= 3;
-      }
-
-      if (fseek(lexer_file, read_start, SEEK_SET) != -1) {
-        size_t bytes_read = fread(p, 1, read_length, lexer_file);
-        if (bytes_read > 0)
-          p += bytes_read;
-      }
-
-      if (has_end_ellipsis) {
-        memcpy(p, "...", 3);
-        p += 3;
-      }
-
-      source_line_length = p - source_line;
-
-      *p = '\0';
-
-      if (fseek(lexer_file, old_offset, SEEK_SET) == -1) {
-        /* we're screwed now, blow up. */
-        WASM_FATAL("failed to seek.");
-      }
+    WasmResult result = wasm_lexer_get_source_line(
+        lexer, loc, source_line_max_length, source_line,
+        &source_line_length, &source_line_column_offset);
+    if (WASM_FAILED(result)) {
+      /* if this fails, it means that we've probably screwed up the lexer. blow
+       * up. */
+      WASM_FATAL("error getting the source line.");
     }
   }
 
   if (error_handler->on_error) {
     error_handler->on_error(loc, buffer, source_line, source_line_length,
-                            source_line_column_offset, error_handler->user_data);
+                            source_line_column_offset,
+                            error_handler->user_data);
   }
   va_end(args_copy);
 }