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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/*
* Test program to mangle 1 bit in a binary
*/
#include "nspr.h"
#include "plstr.h"
#include "plgetopt.h"
#include "prio.h"
static PRFileDesc *pr_stderr;
static void
usage(char *program_name)
{
PR_fprintf(pr_stderr, "Usage:");
PR_fprintf(pr_stderr, "%s -i shared_library_name -o byte_offset -b bit\n", program_name);
}
int
main(int argc, char **argv)
{
/* buffers and locals */
PLOptState *optstate;
char *programName;
char cbuf;
/* parameter set variables */
const char *libFile = NULL;
int bitOffset = -1;
/* return values */
int retval = 2; /* 0 - test succeeded.
* 1 - illegal args
* 2 - function failed */
PRFileDesc *fd = NULL;
int bytesRead;
int bytesWritten;
PROffset32 offset = -1;
PROffset32 pos;
programName = PL_strrchr(argv[0], '/');
programName = programName ? (programName + 1) : argv[0];
pr_stderr = PR_STDERR;
optstate = PL_CreateOptState(argc, argv, "i:o:b:");
if (optstate == NULL) {
return 1;
}
while (PL_GetNextOpt(optstate) == PL_OPT_OK) {
switch (optstate->option) {
case 'i':
libFile = optstate->value;
break;
case 'o':
offset = atoi(optstate->value);
break;
case 'b':
bitOffset = atoi(optstate->value);
break;
}
}
if (libFile == NULL) {
usage(programName);
return 1;
}
if ((bitOffset >= 8) || (bitOffset < 0)) {
usage(programName);
return 1;
}
/* open the target signature file */
fd = PR_OpenFile(libFile, PR_RDWR, 0666);
if (fd == NULL) {
/* lperror(libFile); */
PR_fprintf(pr_stderr, "Couldn't Open %s\n", libFile);
goto loser;
}
if (offset < 0) { /* convert to positive offset */
pos = PR_Seek(fd, offset, PR_SEEK_END);
if (pos == -1) {
PR_fprintf(pr_stderr, "Seek for read on %s (to %d) failed\n",
libFile, offset);
goto loser;
}
offset = pos;
}
/* read the byte */
pos = PR_Seek(fd, offset, PR_SEEK_SET);
if (pos != offset) {
PR_fprintf(pr_stderr, "Seek for read on %s (to %d) failed\n",
libFile, offset);
goto loser;
}
bytesRead = PR_Read(fd, &cbuf, 1);
if (bytesRead != 1) {
PR_fprintf(pr_stderr, "Read on %s (to %d) failed\n", libFile, offset);
goto loser;
}
PR_fprintf(pr_stderr, "Changing byte 0x%08x (%d): from %02x (%d) to ",
offset, offset, (unsigned char)cbuf, (unsigned char)cbuf);
/* change it */
cbuf ^= 1 << bitOffset;
PR_fprintf(pr_stderr, "%02x (%d)\n",
(unsigned char)cbuf, (unsigned char)cbuf);
/* write it back out */
pos = PR_Seek(fd, offset, PR_SEEK_SET);
if (pos != offset) {
PR_fprintf(pr_stderr, "Seek for write on %s (to %d) failed\n",
libFile, offset);
goto loser;
}
bytesWritten = PR_Write(fd, &cbuf, 1);
if (bytesWritten != 1) {
PR_fprintf(pr_stderr, "Write on %s (to %d) failed\n", libFile, offset);
goto loser;
}
retval = 0;
loser:
if (fd)
PR_Close(fd);
PR_Cleanup();
return retval;
}
/*#DEFINES += -DSHLIB_SUFFIX=\"$(DLL_SUFFIX)\" -DSHLIB_PREFIX=\"$(DLL_PREFIX)\" */
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