BSD 4_4_Lite1 development

[unix-history] / usr / src / contrib / rc-1.4 / utils.c

/* utils.c: functions of general utility */

#include <errno.h>
#include <setjmp.h>
#include "rc.h"
#include "jbwrap.h"

/* print error with line number on noninteractive shells (i.e., scripts) */

extern void pr_error(char *s) {
       if (s != NULL) {
               if (interactive)
                       fprint(2, "%s\n", s);
               else
                       fprint(2, "line %d: %s\n", lineno - 1, s);
       }
}

/* our perror */

extern void uerror(char *s) {
       extern int sys_nerr;
       extern char *sys_errlist[];
       if (errno > sys_nerr)
               return;
       if (s != NULL)
               fprint(2, "%s: %s\n", s, sys_errlist[errno]);
       else
               fprint(2, "%s\n", sys_errlist[errno]);
}

/* Die horribly. This should never get called. Please let me know if it does. */

#define PANICMSG "rc panic: "

extern void panic(char *s) {
       write(2, PANICMSG, conststrlen(PANICMSG));
       write(2, s, strlen(s));
       write(2, "!\n", 2);
       exit(1);
}

/* ascii -> unsigned conversion routines. -1 indicates conversion error. */

extern int n2u(char *s, unsigned int base) {
       unsigned int i;
       for (i = 0; *s != '\0'; s++) {
               unsigned int j = (unsigned int) *s - '0';
               if (j >= base) /* small hack with unsigned ints -- one compare for range test */
                       return -1;
               i = i * base + j;
       }
       return (int) i;
}

/* The last word in portable ANSI: a strcmp wrapper for qsort */

extern int starstrcmp(const void *s1, const void *s2) {
       return strcmp(*(char **)s1, *(char **)s2);
}

/* tests to see if pathname begins with "/", "./", or "../" */

extern bool isabsolute(char *path) {
       return path[0] == '/' || (path[0] == '.' && (path[1] == '/' || (path[1] == '.' && path[2] == '/')));
}

/* signal-safe read and write (for BSD slow devices). writeall also allows partial writes */

extern void writeall(int fd, char *buf, size_t remain) {
       int i;
       for (i = 0; remain > 0; buf += i, remain -= i) {
               interrupt_happened = FALSE;
               if (!setjmp(slowbuf.j)) {
                       slow = TRUE;
                       if (interrupt_happened)
                               break;
                       else if ((i = write(fd, buf, remain)) <= 0)
                               break; /* abort silently on errors in write() */
               } else
                       break;
               slow = FALSE;
       }
       slow = FALSE;
       SIGCHK;
}

extern int rc_read(int fd, char *buf, size_t n) {
       long /*ssize_t*/ r;
       interrupt_happened = FALSE;
       if (!setjmp(slowbuf.j)) {
               slow = TRUE;
               if (!interrupt_happened)
                       r = read(fd, buf, n);
               else
                       r = -2;
       } else
               r = -2;
       slow = FALSE;
       if (r == -2) {
               errno = EINTR;
               r = -1;
       }
       SIGCHK;
       return r;
}

/* clear out z bytes from character string s */

extern char *clear(char *s, size_t z) {
       while (z != 0)
               s[--z] = 0;
       return s;
}

/* duplicate a fd and close the old one only if necessary */

extern int mvfd(int i, int j) {
       if (i != j) {
               int s = dup2(i, j);
               close(i);
               return s;
       }
       return 0;
}