docs: add docs for additional libconsensus functions

Co-authored-by: Bruno Garcia <[email protected]>

Author: jrawsthorne

doc/shared-libraries.md

@@ -11,13 +11,14 @@ The interface is defined in the C header `bitcoinconsensus.h` located in `src/sc
 
 #### Version
 
-`bitcoinconsensus_version` returns an `unsigned int` with the API version *(currently `1`)*.
+`bitcoinconsensus_version` returns an `unsigned int` with the API version *(currently `2`)*.
 
 #### Script Validation
 
-`bitcoinconsensus_verify_script` returns an `int` with the status of the verification. It will be `1` if the input script correctly spends the previous output `scriptPubKey`.
+`bitcoinconsensus_verify_script`, `bitcoinconsensus_verify_script_with_amount` and `bitcoinconsensus_verify_script_with_spent_outputs` return an `int` with the status of the verification. It will be `1` if the input script correctly spends the previous output `scriptPubKey`.
 
 ##### Parameters
+###### bitcoinconsensus_verify_script
 - `const unsigned char *scriptPubKey` - The previous output script that encumbers spending.
 - `unsigned int scriptPubKeyLen` - The number of bytes for the `scriptPubKey`.
 - `const unsigned char *txTo` - The transaction with the input that is spending the previous output.
@@ -26,6 +27,28 @@ The interface is defined in the C header `bitcoinconsensus.h` located in `src/sc
 - `unsigned int flags` - The script validation flags *(see below)*.
 - `bitcoinconsensus_error* err` - Will have the error/success code for the operation *(see below)*.
 
+###### bitcoinconsensus_verify_script_with_amount
+- `const unsigned char *scriptPubKey` - The previous output script that encumbers spending.
+- `unsigned int scriptPubKeyLen` - The number of bytes for the `scriptPubKey`.
+- `int64_t amount` - The amount spent in the input
+- `const unsigned char *txTo` - The transaction with the input that is spending the previous output.
+- `unsigned int txToLen` - The number of bytes for the `txTo`.
+- `unsigned int nIn` - The index of the input in `txTo` that spends the `scriptPubKey`.
+- `unsigned int flags` - The script validation flags *(see below)*.
+- `bitcoinconsensus_error* err` - Will have the error/success code for the operation *(see below)*.
+
+###### bitcoinconsensus_verify_script_with_spent_outputs
+- `const unsigned char *scriptPubKey` - The previous output script that encumbers spending.
+- `unsigned int scriptPubKeyLen` - The number of bytes for the `scriptPubKey`.
+- `int64_t amount` - The amount spent in the input
+- `const unsigned char *txTo` - The transaction with the input that is spending the previous output.
+- `unsigned int txToLen` - The number of bytes for the `txTo`.
+- `UTXO *spentOutputs` - Previous outputs spent in the transaction. `UTXO` is a struct composed by `const unsigned char *scriptPubKey`, `unsigned int scriptPubKeySize` (the number of bytes for the `scriptPubKey`) and `unsigned int value`.
+- `unsigned int spentOutputsLen` - The number of bytes for the `spentOutputs`.
+- `unsigned int nIn` - The index of the input in `txTo` that spends the `scriptPubKey`.
+- `unsigned int flags` - The script validation flags *(see below)*.
+- `bitcoinconsensus_error* err` - Will have the error/success code for the operation *(see below)*.
+
 ##### Script Flags
 - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_NONE`
 - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_P2SH` - Evaluate P2SH ([BIP16](https://github.com/bitcoin/bips/blob/master/bip-0016.mediawiki)) subscripts
@@ -34,6 +57,7 @@ The interface is defined in the C header `bitcoinconsensus.h` located in `src/sc
 - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_CHECKLOCKTIMEVERIFY` - Enable CHECKLOCKTIMEVERIFY ([BIP65](https://github.com/bitcoin/bips/blob/master/bip-0065.mediawiki))
 - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_CHECKSEQUENCEVERIFY` - Enable CHECKSEQUENCEVERIFY ([BIP112](https://github.com/bitcoin/bips/blob/master/bip-0112.mediawiki))
 - `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_WITNESS` - Enable WITNESS ([BIP141](https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki))
+- `bitcoinconsensus_SCRIPT_FLAGS_VERIFY_TAPROOT` - Enable TAPROOT ([BIP340](https://github.com/bitcoin/bips/blob/master/bip-0340.mediawiki), [BIP341](https://github.com/bitcoin/bips/blob/master/bip-0341.mediawiki), [BIP342](https://github.com/bitcoin/bips/blob/master/bip-0342.mediawiki))
 
 ##### Errors
 - `bitcoinconsensus_ERR_OK` - No errors with input parameters *(see the return value of `bitcoinconsensus_verify_script` for the verification status)*
@@ -42,6 +66,8 @@ The interface is defined in the C header `bitcoinconsensus.h` located in `src/sc
 - `bitcoinconsensus_ERR_DESERIALIZE` - An error deserializing `txTo`
 - `bitcoinconsensus_ERR_AMOUNT_REQUIRED` - Input amount is required if WITNESS is used
 - `bitcoinconsensus_ERR_INVALID_FLAGS` - Script verification `flags` are invalid (i.e. not part of the libconsensus interface)
+- `bitcoinconsensus_ERR_SPENT_OUTPUTS_REQUIRED` - Spent outputs are required if TAPROOT is used
+- `bitcoinconsensus_ERR_SPENT_OUTPUTS_MISMATCH` - Spent outputs size doesn't match tx inputs size
 
 ### Example Implementations
 - [NBitcoin](https://github.com/MetacoSA/NBitcoin/blob/5e1055cd7c4186dee4227c344af8892aea54faec/NBitcoin/Script.cs#L979-#L1031) (.NET Bindings)