/*

* ex_get_pass.c

*

* Created on: Nov 22, 2010

* Author: bogdan

*/

#define MAX_PASS_LEN 8

#include <signal.h>

#include <termios.h>

#include <stdio.h>

#include <stdlib.h>

char* getpass(const char *prompt)

{

static char buf[MAX_PASS_LEN+1];

char *ptr;

sigset_t sig, osig;

struct termios ts, ots;

FILE *fp;

int c;

if (NULL == (fp = fopen(ctermid(NULL), "r+")))

{

perror("fopen");

return NULL;

}

setbuf(fp, buf);

sigemptyset(&sig);

sigaddset(&sig, SIGINT);

sigaddset(&sig, SIGTSTP);

sigprocmask(SIG_BLOCK, &sig, &osig);

tcgetattr(fileno(fp), &ts);

ots = ts;

ts.c_lflag &= ~(ECHO | ECHOE | ECHOK | ECHONL);

tcsetattr(fileno(fp), TCSAFLUSH, &ts);

fputs(prompt, fp);

ptr = buf;

while ((EOF != (c = getc(fp))) && (c != '\n'))

{

if (ptr < &buf[MAX_PASS_LEN])

{

*ptr++ = c;

}

}

*ptr = 0;

putc('\n', fp);

tcsetattr(fileno(fp), TCSAFLUSH, &ots);

sigprocmask(SIG_SETMASK, &osig, NULL);

fclose(fp);

return buf;

}

int main()

{

char *ptr;

if (NULL == (ptr = getpass("Enter password: ")))

{

fprintf(stderr, "Error in getpass\n");

return EXIT_FAILURE;

}

printf("Password: %s\n", ptr);

//zero out the memory

while (*ptr != 0)

{

*ptr++ = 0;

}

return EXIT_SUCCESS;

}