Merge commits 'c8aa516b 0a40a486 d8a24632 85b00a1c 59547943 5dcc6f8d 07752831 3ef94aa5 1253a277 64b34979 ac83be33 0e5cbd01 e0508ee9 587239db 1ac7e31c d0ad5814 912b7ccc 8746600e ' into temp-merge-1093

Revert: util: Remove endianness detection

include/secp256k1.h

@@ -169,6 +169,17 @@ typedef int (*secp256k1_nonce_function)(
 #  define SECP256K1_ARG_NONNULL(_x)
 # endif
 
+/** Attribute for marking functions, types, and variables as deprecated */
+#if !defined(SECP256K1_BUILD) && defined(__has_attribute)
+# if __has_attribute(__deprecated__)
+#  define SECP256K1_DEPRECATED(_msg) __attribute__ ((__deprecated__(_msg)))
+# else
+#  define SECP256K1_DEPRECATED(_msg)
+# endif
+#else
+# define SECP256K1_DEPRECATED(_msg)
+#endif
+
 /** All flags' lower 8 bits indicate what they're for. Do not use directly. */
 #define SECP256K1_FLAGS_TYPE_MASK ((1 << 8) - 1)
 #define SECP256K1_FLAGS_TYPE_CONTEXT (1 << 0)
@@ -641,7 +652,8 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_seckey_negate(
 SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_negate(
     const secp256k1_context* ctx,
     unsigned char *seckey
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2)
+  SECP256K1_DEPRECATED("Use secp256k1_ec_seckey_negate instead");
 
 /** Negates a public key in place.
  *
@@ -681,7 +693,8 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_add(
     const secp256k1_context* ctx,
     unsigned char *seckey,
     const unsigned char *tweak32
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3)
+  SECP256K1_DEPRECATED("Use secp256k1_ec_seckey_tweak_add instead");
 
 /** Tweak a public key by adding tweak times the generator to it.
  *
@@ -727,7 +740,8 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_privkey_tweak_mul(
     const secp256k1_context* ctx,
     unsigned char *seckey,
     const unsigned char *tweak32
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3)
+  SECP256K1_DEPRECATED("Use secp256k1_ec_seckey_tweak_mul instead");
 
 /** Tweak a public key by multiplying it by a tweak value.
  *
@@ -800,7 +814,7 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_ec_pubkey_combine(
  *  implementations optimized for a specific tag can precompute the SHA256 state
  *  after hashing the tag hashes.
  *
- *  Returns 0 if the arguments are invalid and 1 otherwise.
+ *  Returns: 1 always.
  *  Args:    ctx: pointer to a context object
  *  Out:  hash32: pointer to a 32-byte array to store the resulting hash
  *  In:      tag: pointer to an array containing the tag

include/secp256k1_extrakeys.h

@@ -81,8 +81,7 @@ SECP256K1_API int secp256k1_xonly_pubkey_cmp(
 
 /** Converts a secp256k1_pubkey into a secp256k1_xonly_pubkey.
  *
- *  Returns: 1 if the public key was successfully converted
- *           0 otherwise
+ *  Returns: 1 always.
  *
  *  Args:         ctx: pointer to a context object.
  *  Out: xonly_pubkey: pointer to an x-only public key object for placing the converted public key.
@@ -186,7 +185,7 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_create(
 
 /** Get the secret key from a keypair.
  *
- *  Returns: 0 if the arguments are invalid. 1 otherwise.
+ *  Returns: 1 always.
  *  Args:   ctx: pointer to a context object.
  *  Out: seckey: pointer to a 32-byte buffer for the secret key.
  *  In: keypair: pointer to a keypair.
@@ -199,7 +198,7 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_sec(
 
 /** Get the public key from a keypair.
  *
- *  Returns: 0 if the arguments are invalid. 1 otherwise.
+ *  Returns: 1 always.
  *  Args:    ctx: pointer to a context object.
  *  Out: pubkey: pointer to a pubkey object. If 1 is returned, it is set to
  *               the keypair public key. If not, it's set to an invalid value.
@@ -216,7 +215,7 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_keypair_pub(
  *  This is the same as calling secp256k1_keypair_pub and then
  *  secp256k1_xonly_pubkey_from_pubkey.
  *
- *  Returns: 0 if the arguments are invalid. 1 otherwise.
+ *  Returns: 1 always.
  *  Args:   ctx: pointer to a context object.
  *  Out: pubkey: pointer to an xonly_pubkey object. If 1 is returned, it is set
  *               to the keypair public key after converting it to an

include/secp256k1_schnorrsig.h

@@ -116,7 +116,7 @@ typedef struct {
  *                BIP-340 "Default Signing" for a full explanation of this
  *                argument and for guidance if randomness is expensive.
  */
-SECP256K1_API int secp256k1_schnorrsig_sign(
+SECP256K1_API int secp256k1_schnorrsig_sign32(
     const secp256k1_context* ctx,
     unsigned char *sig64,
     const unsigned char *msg32,
@@ -124,6 +124,17 @@ SECP256K1_API int secp256k1_schnorrsig_sign(
     const unsigned char *aux_rand32
 ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4);
 
+/** Same as secp256k1_schnorrsig_sign32, but DEPRECATED. Will be removed in
+ *  future versions. */
+SECP256K1_API int secp256k1_schnorrsig_sign(
+    const secp256k1_context* ctx,
+    unsigned char *sig64,
+    const unsigned char *msg32,
+    const secp256k1_keypair *keypair,
+    const unsigned char *aux_rand32
+) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3) SECP256K1_ARG_NONNULL(4)
+  SECP256K1_DEPRECATED("Use secp256k1_schnorrsig_sign32 instead");
+
 /** Create a Schnorr signature with a more flexible API.
  *
  *  Same arguments as secp256k1_schnorrsig_sign except that it allows signing