1 files changed, 143 insertions, 0 deletions
diff --git a/post.c b/post.c
new file mode 100644
index 0000000..18cafab
--- /dev/null
+++ b/post.c
@@ -0,0 +1,143 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+
+static uint16_t
+post_parse16(const char *data)
+{
+	uint16_t b1 = (uint16_t)((const uint8_t *)data)[0];
+	uint16_t b2 = (uint16_t)((const uint8_t *)data)[1];
+	b1 = (uint16_t)(b1 << 8);
+	b2 = (uint16_t)(b2 << 0);
+	return (uint16_t)(b1 | b2);
+}
+
+static void
+post_sign16(union {uint16_t u; int16_t s;} *info)
+{
+	info->s = ((info->u >> 15) ? -(int16_t)(~info->u + 1) : (int16_t)info->u);
+}
+
+
+int
+libparsesfnt_parse_post(
+			const char *data, size_t size,
+			struct libparsesfnt_post *infop,
+			const struct libparsesfnt_tabdir_entry *tag)
+{
+	int ret;
+	ret = PARSE(LIBPARSESFNT_POST__, tag->offset, 0, 0, 0, 1, tag);
+	if (!ret) {
+		if (infop->format >> 16 == 2) {
+			if (2 > tag->length - tag->offset)
+				goto ebfont;
+			infop->subtable.v2.number_of_glyphs = post_parse16(&data[tag->offset + 2]);
+		}
+	}
+	return ret;
+
+ebfont:
+	errno = EBFONT;
+	return -1;
+}
+
+
+static int
+post_indices(
+			const char *data, size_t size,
+			uint16_t *indexp,
+			const struct libparsesfnt_tabdir_entry *tag,
+			size_t first, size_t count,
+			size_t offset)
+{
+	if (offset > tag->length || first > (tag->length - offset) / 2)
+		goto ebfont;
+	offset += first * 2;
+	if (count > (tag->length - offset) / 2)
+		goto ebfont;
+	if (tag->offset > size || offset > size - tag->offset)
+		goto ebfont;
+	offset += tag->offset;
+
+	for (; count--; indexp++, offset += 2)
+		*indexp = post_parse16(&data[offset]);
+
+	return 0;
+
+ebfont:
+	errno = EBFONT;
+	return -1;
+}
+
+
+int
+libparsesfnt_parse_post_format_2_0_indices(
+			const char *data, size_t size,
+			uint16_t *indexp,
+			const struct libparsesfnt_tabdir_entry *tag,
+			size_t first, size_t count)
+{
+	return post_indices(data, size, indexp, tag, first, count, 34);
+}
+
+
+int
+libparsesfnt_parse_post_format_2_0_name(
+	const char *data, size_t size,
+	char namep[256],
+	const struct libparsesfnt_tabdir_entry *tag, const struct libparsesfnt_post *post,
+	size_t *offsetp /* start at 0 */)
+{
+	size_t len;
+
+	if (!*offsetp) {
+		if ((size_t)post->subtable.v2.number_of_glyphs > ((size_t)tag->length - 34) / 2)
+			goto ebfont;
+		*offsetp = 34 + (size_t)post->subtable.v2.number_of_glyphs / 2;
+		if ((size_t)tag->length > size - (size_t)tag->offset)
+			goto ebfont;
+	}
+
+	if (*offsetp >= (size_t)tag->length)
+		goto ebfont;
+	len = (size_t)*(const uint8_t *)&data[*offsetp];
+	*offsetp += 1;
+
+	if (len > (size_t)tag->length - *offsetp)
+		goto ebfont;
+	memcpy(namep, &data[*offsetp], len);
+	namep[len] = 0;
+	*offsetp += len;
+
+	return 0;
+
+ebfont:
+	errno = EBFONT;
+	return -1;
+}
+
+
+int
+libparsesfnt_parse_post_format_2_5_offsets(
+			const char *data, size_t size,
+			int16_t *offsetp,
+			const struct libparsesfnt_tabdir_entry *tag,
+			size_t first, size_t count)
+{
+	if (post_indices(data, size, (uint16_t *)offsetp, tag, first, count, 34))
+		return -1;
+	for (; count--; offsetp++)
+		post_sign16((void *)offsetp);
+	return 0;
+}
+
+
+int
+libparsesfnt_parse_post_format_4_0_indices(
+			const char *data, size_t size,
+			uint16_t *indexp,
+			const struct libparsesfnt_tabdir_entry *tag,
+			size_t first, size_t count)
+{
+	return post_indices(data, size, indexp, tag, first, count, 32);
+}