bitmap handling routines

1 files changed, 70 insertions, 0 deletions

diff --git a/lpg/libqr/qr-bitmap.c b/lpg/libqr/qr-bitmap.c
new file mode 100644
index 0000000..e42b550
--- /dev/null
+++ b/lpg/libqr/qr-bitmap.c
@@ -0,0 +1,70 @@
+#include <assert.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+#include "qr-bitmap.h"
+
+struct qr_bitmap * qr_bitmap_create(int width, int height, int masked)
+{
+        struct qr_bitmap * out;
+        size_t size;
+
+        out = malloc(sizeof(*out));
+        if (!out)
+                goto fail;
+
+        out->width = width;
+        out->height = height;
+        out->stride = (width / CHAR_BIT) + (width % CHAR_BIT ? 1 : 0);
+
+        size = out->stride * height;
+
+        out->mask = 0;
+        out->bits = malloc(size);
+        if (!out->bits)
+                goto fail;
+        memset(out->bits, 0, size);
+
+        if (masked) {
+                out->mask = malloc(out->stride * width);
+                if (!out->mask)
+                        goto fail;
+                memset(out->bits, 0xFF, size);
+        }
+
+        return out;
+
+fail:
+        qr_bitmap_destroy(out);
+        return 0;
+}
+
+void qr_bitmap_destroy(struct qr_bitmap * bmp)
+{
+        if (bmp) {
+                free(bmp->bits);
+                free(bmp->mask);
+                free(bmp);
+        }
+}
+
+void qr_bitmap_merge(struct qr_bitmap * dest, const struct qr_bitmap * src)
+{
+        unsigned char * d, * s, * m;
+        size_t n;
+
+        assert(dest->stride == src->stride);
+        assert(dest->height == src->height);
+        assert(src->mask);
+
+        n = dest->stride * dest->height;
+        d = dest->bits;
+        s = src->bits;
+        m = src->mask;
+
+        while (n--) {
+                *d   &= ~*m;
+                *d++ |= *s++ & *m++;
+        }
+}
+