The bytestring class provides methods for manipulating byte strings.
In addition to some unique methods, analogs for the standard C "memory" functions are provided. However, unlike the standard C functions, the bytestring methods are NULL safe. Your application will not crash if a NULL is passed in, and instead, will give intuitive results.
The bytestring class provides methods for zeroing, initializing, duplicating, and copying byte strings.
#include <rudiments/bytestring.h>
#include <rudiments/stdio.h>
int main(int argc, const char **argv) {
unsigned char buffer[9];
// zero the buffer
bytestring::zero(buffer,sizeof(buffer));
stdoutput.write("all zeros:\n ");
stdoutput.safePrint(buffer,sizeof(buffer));
stdoutput.write("\n\n");
// set the buffer to all ones
bytestring::set(buffer,1,sizeof(buffer));
stdoutput.write("all ones:\n ");
stdoutput.safePrint(buffer,sizeof(buffer));
stdoutput.write("\n\n");
// copy some data into the buffer
unsigned char data[]={0,1,2,3,4,5,6,7,8};
bytestring::copy(buffer,data,sizeof(data));
stdoutput.write("after copying 0-8:\n ");
stdoutput.safePrint(buffer,sizeof(buffer));
stdoutput.write("\n\n");
// copy some overlapping data from one part of the buffer to another
bytestring::copyWithOverlap(buffer,buffer+3,sizeof(buffer)-3);
stdoutput.write("after copying with overlap:\n ");
stdoutput.safePrint(buffer,sizeof(buffer));
stdoutput.write("\n\n");
// copy a string into the buffer
unsigned char str[]="hello";
bytestring::copyUntil(buffer,str,'\0',sizeof(str));
stdoutput.write("after copying \"hello\":\n ");
stdoutput.safePrint(buffer,sizeof(buffer));
stdoutput.write("\n\n");
// copy some data into the buffer, swapping bytes as they are copied
bytestring::copySwapBytes(buffer,data,sizeof(data));
stdoutput.write("after copying 0-8, swapping bytes:\n ");
stdoutput.safePrint(buffer,sizeof(buffer));
stdoutput.write("\n\n");
}
The bytestring class also provides a compare() method for comparing two byte strings.
#include <rudiments/bytestring.h>
#include <rudiments/stdio.h>
int main(int argc, const char **argv) {
unsigned char buffer1[8];
unsigned char buffer2[8];
// zero the buffers
bytestring::zero(buffer1,sizeof(buffer1));
bytestring::zero(buffer2,sizeof(buffer2));
stdoutput.write("both zeroed:\n");
stdoutput.printf(" does buffer1=buffer2? %s\n\n",
(!bytestring::compare(buffer1,buffer2,sizeof(buffer1)))?
"yes":"no");
// set buffer2 to all ones
bytestring::set(buffer2,1,sizeof(buffer2));
stdoutput.write("buffer2 is all ones:\n");
stdoutput.printf(" does buffer1=buffer2? %s\n\n",
(!bytestring::compare(buffer1,buffer2,sizeof(buffer1)))?
"yes":"no");
// set the first half of buffer2 to zeros
// and only compare the first half
bytestring::set(buffer2,0,sizeof(buffer2)/2);
stdoutput.write("first half of buffer2 is all zeros:\n");
stdoutput.printf(" does 1/2 buffer1 = 1/2 buffer2? %s\n\n",
(!bytestring::compare(buffer1,buffer2,sizeof(buffer1)/2))?
"yes":"no");
}
The charstring class also provides methods for finding characters or other character strings within character strings.
The findFirst() and findLast() methods return the first/last instance of a character or byte string within a byte string, or NULL if no match is found.
#include <rudiments/bytestring.h>
#include <rudiments/stdio.h>
int main(int argc, const char **argv) {
// initialize buffer
unsigned char buffer[]={0,2,0,2,0,2,0};
stdoutput.write("buffer : ");
stdoutput.safePrint(buffer,sizeof(buffer));
stdoutput.write("\n\n");
// find first and last 0
unsigned char *firstzero=(unsigned char *)
bytestring::findFirst(buffer,0,sizeof(buffer));
unsigned char *lastzero=(unsigned char *)
bytestring::findLast(buffer,0,sizeof(buffer));
stdoutput.write("first 0 : ");
stdoutput.safePrint(firstzero,sizeof(buffer)-(firstzero-buffer));
stdoutput.write('\n');
stdoutput.write(" last 0 : ");
stdoutput.safePrint(lastzero,sizeof(buffer)-(lastzero-buffer));
stdoutput.write("\n\n");
// find first and last 0,2,0 patterns
unsigned char pattern[]={0,2,0};
unsigned char *firstzerotwozero=(unsigned char *)
bytestring::findFirst(buffer,sizeof(buffer),
pattern,sizeof(pattern));
unsigned char *lastzerotwozero=(unsigned char *)
bytestring::findLast(buffer,sizeof(buffer),
pattern,sizeof(pattern));
stdoutput.write("first 0,2,0 : ");
stdoutput.safePrint(firstzerotwozero,
sizeof(buffer)-(firstzerotwozero-buffer));
stdoutput.write('\n');
stdoutput.write(" last 0,2,0 : ");
stdoutput.safePrint(lastzerotwozero,
sizeof(buffer)-(lastzerotwozero-buffer));
stdoutput.write("\n\n");
}