move vendor/secp256k1-0.3.0 to vendor/secp256k1/repo

vendor/secp256k1/repo/src/scratch.h

@@ -0,0 +1,42 @@
+/***********************************************************************
+ * Copyright (c) 2017 Andrew Poelstra                                  *
+ * Distributed under the MIT software license, see the accompanying    *
+ * file COPYING or https://www.opensource.org/licenses/mit-license.php.*
+ ***********************************************************************/
+
+#ifndef SECP256K1_SCRATCH_H
+#define SECP256K1_SCRATCH_H
+
+/* The typedef is used internally; the struct name is used in the public API
+ * (where it is exposed as a different typedef) */
+typedef struct secp256k1_scratch_space_struct {
+    /** guard against interpreting this object as other types */
+    unsigned char magic[8];
+    /** actual allocated data */
+    void *data;
+    /** amount that has been allocated (i.e. `data + offset` is the next
+     *  available pointer)  */
+    size_t alloc_size;
+    /** maximum size available to allocate */
+    size_t max_size;
+} secp256k1_scratch;
+
+static secp256k1_scratch* secp256k1_scratch_create(const secp256k1_callback* error_callback, size_t max_size);
+
+static void secp256k1_scratch_destroy(const secp256k1_callback* error_callback, secp256k1_scratch* scratch);
+
+/** Returns an opaque object used to "checkpoint" a scratch space. Used
+ *  with `secp256k1_scratch_apply_checkpoint` to undo allocations. */
+static size_t secp256k1_scratch_checkpoint(const secp256k1_callback* error_callback, const secp256k1_scratch* scratch);
+
+/** Applies a check point received from `secp256k1_scratch_checkpoint`,
+ *  undoing all allocations since that point. */
+static void secp256k1_scratch_apply_checkpoint(const secp256k1_callback* error_callback, secp256k1_scratch* scratch, size_t checkpoint);
+
+/** Returns the maximum allocation the scratch space will allow */
+static size_t secp256k1_scratch_max_allocation(const secp256k1_callback* error_callback, const secp256k1_scratch* scratch, size_t n_objects);
+
+/** Returns a pointer into the most recently allocated frame, or NULL if there is insufficient available space */
+static void *secp256k1_scratch_alloc(const secp256k1_callback* error_callback, secp256k1_scratch* scratch, size_t n);
+
+#endif