1 files changed, 113 insertions, 0 deletions
diff --git a/libmkv/common.h b/libmkv/common.h
new file mode 100644
index 0000000..996eca6
--- /dev/null
+++ b/libmkv/common.h
@@ -0,0 +1,113 @@
+#include <assert.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>   /* for perror() */
+#include <string.h>  /* for memcpy() */
+#include <stdlib.h>  /* for realloc(), free() */
+#include <unistd.h>  /* for write() */
+
+#define LM_ARRAY_LEN(ary)       (sizeof(ary)/sizeof((ary)[0]))
+#define LM_CEILDIV(n, d)        ( ((n)+(d)-1) / (d) )
+#define LM_NEXT_POWER_OF_2(x)   ( (x) ? 1ULL<<((sizeof(unsigned long long)*8)-__builtin_clzll(x)) : 1)
+#define LM_CAT2(a, b)           a ## b
+#define LM_CAT2_(a, b)          LM_CAT2(a, b)
+#define assert_notreached(msg)  assert(false)
+
+struct buf {
+	uint8_t *dat;
+	size_t   len;
+	size_t   cap;
+};
+
+static void append(struct buf *buf, void *dat, size_t len) {
+	assert(buf);
+	assert(len == 0 || dat);
+
+	if (buf->len + len > buf->cap) {
+		buf->cap = LM_NEXT_POWER_OF_2(buf->len + len);
+		buf->dat = realloc(buf->dat, buf->cap);
+		assert(buf->dat);
+	}
+	memcpy(&buf->dat[buf->len], dat, len);
+	buf->len += len;
+}
+
+static void append_u32be(struct buf *buf, uint32_t val) {
+	assert(buf);
+
+	uint8_t dat[4] = {
+		(val>>(8*3))&0xFF,
+		(val>>(8*2))&0xFF,
+		(val>>(8*1))&0xFF,
+		(val>>(8*0))&0xFF,
+	};
+	append(buf, dat, sizeof(dat));
+}
+
+static bool xwrite(int fd, uint8_t *dat, size_t len) {
+	assert(len == 0 || dat);
+
+	for (size_t done = 0; done < len;) {
+		ssize_t n = write(fd, &dat[done], len-done);
+		if (n < 0) {
+			perror("write");
+			return true;
+		}
+		done += n;
+	}
+	return false;
+}
+
+static char font[10][8*4] = {
+	"   ##   "
+	"  #  #  "
+	"  #  #  "
+	"   ##   ",
+
+	"    #   "
+	"   ##   "
+	"    #   "
+	"   ###  ",
+
+	"   ##   "
+	"  #  #  "
+	"    #   "
+	"  ####  ",
+
+	"   ##   "
+	"     #  "
+	"     #  "
+	"   ##   ",
+
+	"    ##  "
+	"   # #  "
+	"  ####  "
+	"     #  ",
+
+	"  ####  "
+	"  ###   "
+	"     #  "
+	"  ###   ",
+
+	"  #     "
+	"  ###   "
+	"  #  #  "
+	"   ##   ",
+
+	"  ####  "
+	"    #   "
+	"   #    "
+	"   #    ",
+
+	"   ##   "
+	"  #  #  "
+	"  ####  "
+	"   ##   ",
+
+	"   ##   "
+	"  #  #  "
+	"   ###  "
+	"     #  ",
+};
+static_assert(LM_ARRAY_LEN(font) == 10);
+static_assert(sizeof(font[0]) == 32);