Initial import of NFC GNSS SDK project

ql-config/soc_platform/preboot_boot2/sys/include/shmrb.h

@@ -0,0 +1,70 @@
+#ifndef __SHMRB_H__
+#define __SHMRB_H__
+
+#include <stdlib.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct {
+    unsigned wptr;
+    unsigned rptr;
+    char *buf;
+    unsigned size;
+} shmrb_t;
+
+/**
+ * Initialize a shmrb.
+ * rb     Datum to initialize.
+ * buf    Buffer to use by rb.
+ * size   size of (buf)
+ */
+static inline void shmrb_init (shmrb_t * rb, char *buf, unsigned size)
+{
+    rb->buf = buf;
+    rb->size = size;
+    rb->wptr = 0;
+    rb->rptr = 0;
+}
+
+/**
+ * Add a number of elements to the shmrb.
+ * Return the number of elements actually added.
+ */
+size_t shmrb_add(shmrb_t *rb, const char *buf, size_t n);
+
+/**
+ * Read and remove a number of elements from the shmrb.
+ * Return the number of elements actually read.
+ */
+size_t shmrb_get(shmrb_t *rb, char *buf, size_t n);
+
+/**
+ * Return available element in shmrb
+ */
+static inline size_t shmrb_get_avail(const shmrb_t *rb)
+{
+    int size = rb->wptr - rb->rptr;
+
+    if (size < 0) {
+        size += rb->size;
+    }
+
+    return (size_t)size;
+}
+
+/**
+ * Return available space in shmrb
+ */
+static inline size_t shmrb_get_free(const shmrb_t *rb)
+{
+    return (size_t)((rb->size - 1) - shmrb_get_avail(rb));
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+/** @} */
+#endif /* __SHMRB_H__ */