Rename perturb to permute.

Perturb is a bit stretched for this, permute is better.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

Makefile

@@ -5,7 +5,7 @@ PROTOCC:=protoc-c
 
 PROGRAMS := open-channel open-anchor-sig leak-anchor-sigs
 
-HELPER_OBJS := base58.o lightning.pb-c.o shadouble.o pkt.o bitcoin_script.o perturb.o signature.o bitcoin_tx.o bitcoin_address.o anchor.o
+HELPER_OBJS := base58.o lightning.pb-c.o shadouble.o pkt.o bitcoin_script.o permute_tx.o signature.o bitcoin_tx.o bitcoin_address.o anchor.o
 
 CCAN_OBJS := ccan-crypto-sha256.o ccan-crypto-shachain.o ccan-err.o ccan-tal.o ccan-tal-str.o ccan-take.o ccan-list.o ccan-str.o ccan-opt-helpers.o ccan-opt.o ccan-opt-parse.o ccan-opt-usage.o ccan-read_write_all.o ccan-str-hex.o ccan-tal-grab_file.o ccan-noerr.o
 

anchor.c

@@ -2,7 +2,7 @@
 #include "bitcoin_tx.h"
 #include "overflows.h"
 #include "pkt.h"
-#include "perturb.h"
+#include "permute_tx.h"
 #include "bitcoin_script.h"
 
 struct bitcoin_tx *anchor_tx_create(const tal_t *ctx,
@@ -81,9 +81,9 @@ struct bitcoin_tx *anchor_tx_create(const tal_t *ctx,
 	else
 		outmap = NULL;
 		
-	perturb_inputs(o1->seed, o2->seed, 0, tx->input, tx->input_count,
+	permute_inputs(o1->seed, o2->seed, 0, tx->input, tx->input_count,
 		       inmap);
-	perturb_outputs(o1->seed, o2->seed, 0, tx->output, tx->output_count,
+	permute_outputs(o1->seed, o2->seed, 0, tx->output, tx->output_count,
 			outmap);
 	return tx;
 }

perturb.c → permute_tx.c

@@ -1,4 +1,4 @@
-#include "perturb.h"
+#include "permute_tx.h"
 #include <ccan/crypto/sha256/sha256.h>
 #include <stdbool.h>
 #include <string.h>
@@ -16,7 +16,7 @@ static u32 get_next_rand(struct sha256 *h, size_t *randidx)
 static void init_rand(struct sha256 *h, size_t *randidx,
 		      uint64_t seed1, uint64_t seed2,
 		      uint64_t transaction_num,
-		      enum perturb_style style)
+		      enum permute_style style)
 {
 	struct sha256_ctx shactx;
 
@@ -93,7 +93,7 @@ static void swap_inputs(struct bitcoin_tx_input *inputs, size_t *map,
 	}
 }
 
-void perturb_inputs(uint64_t seed1, uint64_t seed2, uint64_t tx_num,
+void permute_inputs(uint64_t seed1, uint64_t seed2, uint64_t tx_num,
 		    struct bitcoin_tx_input *inputs,
 		    size_t num_inputs,
 		    size_t *map)
@@ -110,7 +110,7 @@ void perturb_inputs(uint64_t seed1, uint64_t seed2, uint64_t tx_num,
 			    i, i + find_best_in(inputs + i, num_inputs - i));
 	}
 
-	init_rand(&h, &randidx, seed1, seed2, tx_num, PERTURB_INPUT_STYLE);
+	init_rand(&h, &randidx, seed1, seed2, tx_num, PERMUTE_INPUT_STYLE);
 		  
 	/* Now, Fisher-Yates shuffle, but using SHA256 as "random" source. */
 	for (i = 0; i + 1 < num_inputs; i++) {
@@ -159,7 +159,7 @@ static size_t find_best_out(struct bitcoin_tx_output *outputs, size_t num)
 	return best;
 }
 
-void perturb_outputs(uint64_t seed1, uint64_t seed2, size_t tx_num,
+void permute_outputs(uint64_t seed1, uint64_t seed2, size_t tx_num,
 		     struct bitcoin_tx_output *outputs,
 		     size_t num_outputs,
 		     size_t *map)
@@ -176,7 +176,7 @@ void perturb_outputs(uint64_t seed1, uint64_t seed2, size_t tx_num,
 			     i, i + find_best_out(outputs + i, num_outputs - i));
 	}
 
-	init_rand(&h, &randidx, seed1, seed2, tx_num, PERTURB_OUTPUT_STYLE);
+	init_rand(&h, &randidx, seed1, seed2, tx_num, PERMUTE_OUTPUT_STYLE);
 		  
 	/* Now, Fisher-Yates shuffle, but using SHA256 as "random" source. */
 	for (i = 0; i + 1 < num_outputs; i++) {

permute_tx.h

@@ -0,0 +1,25 @@
+#ifndef LIGHTNING_PERMUTE_TX_H
+#define LIGHTNING_PERMUTE_TX_H
+#include "bitcoin_tx.h"
+
+/* Given the two seeds, permute the transaction inputs.
+ * map[0] is set to the new index of input 0, etc.
+ */
+void permute_inputs(uint64_t seed1, uint64_t seed2,
+		    size_t transaction_num,
+		    struct bitcoin_tx_input *inputs,
+		    size_t num_inputs,
+		    size_t *map);
+
+void permute_outputs(uint64_t seed1, uint64_t seed2,
+		     size_t transaction_num,
+		     struct bitcoin_tx_output *outputs,
+		     size_t num_outputs,
+		     size_t *map);
+
+enum permute_style {
+	PERMUTE_INPUT_STYLE = 0,
+	PERMUTE_OUTPUT_STYLE = 1
+};
+
+#endif /* LIGHTNING_PERMUTE_TX_H */

perturb.h

@@ -1,25 +0,0 @@
-#ifndef LIGHTNING_PERTURB_H
-#define LIGHTNING_PERTURB_H
-#include "bitcoin_tx.h"
-
-/* Given the two seeds, perturb the transaction inputs.
- * map[0] is set to the new index of input 0, etc.
- */
-void perturb_inputs(uint64_t seed1, uint64_t seed2,
-		    size_t transaction_num,
-		    struct bitcoin_tx_input *inputs,
-		    size_t num_inputs,
-		    size_t *map);
-
-void perturb_outputs(uint64_t seed1, uint64_t seed2,
-		     size_t transaction_num,
-		     struct bitcoin_tx_output *outputs,
-		     size_t num_outputs,
-		     size_t *map);
-
-enum perturb_style {
-	PERTURB_INPUT_STYLE = 0,
-	PERTURB_OUTPUT_STYLE = 1
-};
-
-#endif /* LIGHTNING_PERTURB_H */