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#include <u.h>
#include <libc.h>
#include "drawterm.h"
void*
erealloc(void *v, ulong n)
{
v = realloc(v, n);
if(v == nil)
sysfatal("out of memory");
return v;
}
char*
estrdup(char *s)
{
s = strdup(s);
if(s == nil)
sysfatal("out of memory");
return s;
}
char*
estrappend(char *s, char *fmt, ...)
{
char *t;
va_list arg;
va_start(arg, fmt);
t = vsmprint(fmt, arg);
if(t == nil)
sysfatal("out of memory");
va_end(arg);
s = erealloc(s, strlen(s)+strlen(t)+1);
strcat(s, t);
free(t);
return s;
}
/*
* prompt for a string with a possible default response
*/
char*
readcons(char *prompt, char *def, int raw)
{
int fdin, fdout, ctl, n;
char line[10];
char *s;
fdin = open("/dev/cons", OREAD);
if(fdin < 0)
fdin = 0;
fdout = open("/dev/cons", OWRITE);
if(fdout < 0)
fdout = 1;
if(def != nil)
fprint(fdout, "%s[%s]: ", prompt, def);
else
fprint(fdout, "%s: ", prompt);
if(raw){
ctl = open("/dev/consctl", OWRITE);
if(ctl >= 0)
write(ctl, "rawon", 5);
} else
ctl = -1;
s = estrdup("");
for(;;){
n = read(fdin, line, 1);
if(n == 0){
Error:
close(fdin);
close(fdout);
if(ctl >= 0)
close(ctl);
free(s);
return nil;
}
if(n < 0)
goto Error;
if(line[0] == 0x7f)
goto Error;
if(n == 0 || line[0] == '\n' || line[0] == '\r'){
if(raw){
write(ctl, "rawoff", 6);
write(fdout, "\n", 1);
}
close(ctl);
close(fdin);
close(fdout);
if(*s == 0 && def != nil)
s = estrappend(s, "%s", def);
return s;
}
if(line[0] == '\b'){
if(strlen(s) > 0)
s[strlen(s)-1] = 0;
} else if(line[0] == 0x15) { /* ^U: line kill */
if(def != nil)
fprint(fdout, "\n%s[%s]: ", prompt, def);
else
fprint(fdout, "\n%s: ", prompt);
s[0] = 0;
} else {
s = estrappend(s, "%c", line[0]);
}
}
return nil; /* not reached */
}
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