Use separate function to append newlines
* SPDX-License-Identifier: MIT
*/
+#include <assert.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
@@ -110,6 +111,21 @@ void yy_delete_buffer(YY_BUFFER_STATE buf)
free(buf);
}
+/*
+ * Maintains the following invariants:
+ * 1. nBufferSize < capacity
+ * 2. The buffer is terminated with 0
+ * 3. nBufferSize is the size without the terminator
+ */
+static void yy_buffer_append(YY_BUFFER_STATE buf, uint32_t capacity, char c)
+{
+ assert(buf->pBuffer[buf->nBufferSize] == 0);
+ assert(buf->nBufferSize + 1 < capacity);
+
+ buf->pBuffer[buf->nBufferSize++] = c;
+ buf->pBuffer[buf->nBufferSize] = 0;
+}
+
YY_BUFFER_STATE yy_scan_bytes(char *mem, uint32_t size)
{
YY_BUFFER_STATE pBuffer = malloc(sizeof(struct yy_buffer_state));
@@ -145,7 +161,10 @@ YY_BUFFER_STATE yy_create_buffer(FILE *f)
size = ftell(f);
fseek(f, 0, SEEK_SET);
- pBuffer->pBufferRealStart = malloc(size + 3 + SAFETYMARGIN);
+ /* Give extra room for 2 newlines and terminator */
+ uint32_t capacity = size + 3;
+
+ pBuffer->pBufferRealStart = malloc(capacity + SAFETYMARGIN);
if (pBuffer->pBufferRealStart == NULL)
fatalerror("%s: Out of memory for buffer!", __func__);
@@ -156,6 +175,7 @@ YY_BUFFER_STATE yy_create_buffer(FILE *f)
size = fread(pBuffer->pBuffer, sizeof(uint8_t), size, f);
pBuffer->pBuffer[size] = 0;
+ pBuffer->nBufferSize = size;
/* Convert all line endings to LF and spaces */
@@ -216,13 +236,9 @@ YY_BUFFER_STATE yy_create_buffer(FILE *f)
}
}
- pBuffer->nBufferSize = size;
-
/* Add newline if file doesn't end with one */
- if (size == 0 || pBuffer->pBuffer[size - 1] != '\n') {
- pBuffer->pBuffer[pBuffer->nBufferSize] = '\n';
- pBuffer->nBufferSize++;
- }
+ if (size == 0 || pBuffer->pBuffer[size - 1] != '\n')
+ yy_buffer_append(pBuffer, capacity, '\n');
/* Add newline if \ will eat the last newline */
if (pBuffer->nBufferSize >= 2) {
@@ -232,14 +248,10 @@ YY_BUFFER_STATE yy_create_buffer(FILE *f)
while (pos > 0 && pBuffer->pBuffer[pos] == ' ')
pos--;
- if (pBuffer->pBuffer[pos] == '\\') {
- pBuffer->pBuffer[pBuffer->nBufferSize] = '\n';
- pBuffer->nBufferSize++;
- }
+ if (pBuffer->pBuffer[pos] == '\\')
+ yy_buffer_append(pBuffer, capacity, '\n');
}
- pBuffer->pBuffer[pBuffer->nBufferSize] = 0;
-
pBuffer->oAtLineStart = 1;
return pBuffer;
}
