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Minior cleanups -- removed commented out debugging code, wrote better

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(ugha)
This commit is contained in:
ugha
2004-07-12 05:12:22 +00:00
committed by zzz
parent 0f60ac5acf
commit f2f26136c1
1 changed files with 40 additions and 34 deletions
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74
core/c/src/jbigi.c
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@ -2,15 +2,12 @@
#include <gmp.h>
#include "jbigi.h"
/********/
//function prototypes
//FIXME: should these go into jbigi.h? -- ughabugha
/******** prototypes */
void convert_j2mp(JNIEnv* env, jbyteArray jvalue, mpz_t* mvalue);
void convert_mp2j(JNIEnv* env, mpz_t mvalue, jbyteArray* jvalue);
/********/
/******** nativeModPow() */
/*
* Class: net_i2p_util_NativeBigInteger
* Method: nativeModPow
@ -27,47 +24,41 @@ void convert_mp2j(JNIEnv* env, mpz_t mvalue, jbyteArray* jvalue);
JNIEXPORT jbyteArray JNICALL Java_net_i2p_util_NativeBigInteger_nativeModPow
(JNIEnv* env, jclass cls, jbyteArray jbase, jbyteArray jexp, jbyteArray jmod) {
// convert base, exponent, modulus into the format libgmp understands
// call libgmp's modPow
// convert libgmp's result into a big endian twos complement number
/* 1) Convert base, exponent, modulus into the format libgmp understands
* 2) Call libgmp's modPow.
* 3) Convert libgmp's result into a big endian twos complement number.
*
* Luckily we can use GMP's mpz_import() and mpz_export() functions.
*/
mpz_t mbase;
mpz_t mexp;
mpz_t mmod;
//mpz_t mresult;
jbyteArray jresult;
convert_j2mp(env, jbase, &mbase);
convert_j2mp(env, jexp, &mexp);
convert_j2mp(env, jmod, &mmod);
//gmp_printf("mbase =%Zd\n", mbase);
//gmp_printf("mexp =%Zd\n", mexp);
//gmp_printf("mmod =%Zd\n", mmod);
/* Perform the actual powmod. We use mmod for the result because it is
* always at least as big as the result.
*/
mpz_powm(mmod, mbase, mexp, mmod);
//we use mod for the result because it is always at least as big
//gmp_printf("mresult=%Zd\n", mmod);
convert_mp2j(env, mmod, &jresult);
//convert_j2mp(env, jresult, &mresult);
//gmp_printf("", mpz_cmp(mmod, mresult) == 0 ? "true" : "false");
mpz_clear(mbase);
mpz_clear(mexp);
mpz_clear(mmod);
//mpz_clear(mresult);
return jresult;
}
/********/
/******** convert_j2mp() */
/*
* Initializes the GMP value with enough preallocated size, and converts the
* Java value into the GMP value. The value that mvalue is pointint to
* should be uninitialized
* Java value into the GMP value. The value that mvalue points to should be
* uninitialized
*/
void convert_j2mp(JNIEnv* env, jbyteArray jvalue, mpz_t* mvalue)
@ -81,18 +72,29 @@ void convert_j2mp(JNIEnv* env, jbyteArray jvalue, mpz_t* mvalue)
mpz_init2(*mvalue, sizeof(jbyte) * 8 * size); //preallocate the size
/*
* void mpz_import (mpz_t rop, size_t count, int order, int size, int endian, size_t nails, const void *op)
* order = 1 - order can be 1 for most significant word first or -1 for least significant first.
* endian = 1 - Within each word endian can be 1 for most significant byte first, -1 for least significant first
* nails = 0 - The most significant nails bits of each word are skipped, this can be 0 to use the full words
* void mpz_import(
* mpz_t rop, size_t count, int order, int size, int endian,
* size_t nails, const void *op);
*
* order = 1
* order can be 1 for most significant word first or -1 for least
* significant first.
* endian = 1
* Within each word endian can be 1 for most significant byte first,
* -1 for least significant first.
* nails = 0
* The most significant nails bits of each word are skipped, this can
* be 0 to use the full words.
*/
mpz_import(*mvalue, size, 1, sizeof(jbyte), 1, 0, (void*)jbuffer);
(*env)->ReleaseByteArrayElements(env, jvalue, jbuffer, JNI_ABORT);
}
/********/
/******** convert_mp2j() */
/*
* Converts the GMP value into the Java value; Doesn't do anything else.
* Pads the resulting jbyte array with 0, so the twos complement value is always
* positive.
*/
void convert_mp2j(JNIEnv* env, mpz_t mvalue, jbyteArray* jvalue)
@ -103,21 +105,25 @@ void convert_mp2j(JNIEnv* env, mpz_t mvalue, jbyteArray* jvalue)
copy = JNI_FALSE;
size = (mpz_sizeinbase(mvalue, 2) + 7) / 8 + sizeof(jbyte); //+7 => ceil division
/* sizeinbase() + 7 => Ceil division */
size = (mpz_sizeinbase(mvalue, 2) + 7) / 8 + sizeof(jbyte);
*jvalue = (*env)->NewByteArray(env, size);
buffer = (*env)->GetByteArrayElements(env, *jvalue, &copy);
buffer[0] = 0;
buffer[0] = 0x00;
/*
* void *mpz_export (void *rop, size_t *count, int order, int size, int endian, size_t nails, mpz_t op)
* void *mpz_export(
* void *rop, size_t *count, int order, int size,
* int endian, size_t nails, mpz_t op);
*/
mpz_export((void*)&buffer[1], &size, 1, sizeof(jbyte), 1, 0, mvalue);
/* mode has (supposedly) no effect if elems is not a copy of the
* elements in array
*/
(*env)->ReleaseByteArrayElements(env, *jvalue, buffer, 0);
//mode has (supposedly) no effect if elems is not a copy of the elements in array
}
/********/
/******** eof */