ref: 6af132daa2d80608eeb817b461235af278f6aea8
dir: /readcons.c/
#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 */ }