/* $OpenBSD: printf.c,v 1.22 2014/05/25 07:36:36 jmc Exp $ */ /* * Copyright (c) 1989 The Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <ctype.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include <limits.h> #include <locale.h> #include <errno.h> #include <err.h> static int print_escape_str(const char *); static int print_escape(const char *); static int getchr(void); static double getdouble(void); static int getint(void); static long getlong(void); static unsigned long getulong(void); static char *getstr(void); static char *mklong(const char *, int); static void check_conversion(const char *, const char *); static void usage(void); static int rval; static char **gargv; #define isodigit(c) ((c) >= '0' && (c) <= '7') #define octtobin(c) ((c) - '0') #define hextobin(c) ((c) >= 'A' && (c) <= 'F' ? c - 'A' + 10 : (c) >= 'a' && (c) <= 'f' ? c - 'a' + 10 : c - '0') #define PF(f, func) { \ if (havefieldwidth) \ if (haveprecision) \ (void)printf(f, fieldwidth, precision, func); \ else \ (void)printf(f, fieldwidth, func); \ else if (haveprecision) \ (void)printf(f, precision, func); \ else \ (void)printf(f, func); \ } int main(int argc, char *argv[]) { char *fmt, *start; int havefieldwidth, haveprecision; int fieldwidth, precision; char convch, nextch; char *format; setlocale (LC_ALL, ""); /* Need to accept/ignore "--" option. */ if (argc > 1 && strcmp(argv[1], "--") == 0) { argc--; argv++; } if (argc < 2) { usage(); return (1); } format = *++argv; gargv = ++argv; #define SKIP1 "#-+ 0" #define SKIP2 "0123456789" do { /* * Basic algorithm is to scan the format string for conversion * specifications -- once one is found, find out if the field * width or precision is a '*'; if it is, gather up value. * Note, format strings are reused as necessary to use up the * provided arguments, arguments of zero/null string are * provided to use up the format string. */ /* find next format specification */ for (fmt = format; *fmt; fmt++) { switch (*fmt) { case '%': start = fmt++; if (*fmt == '%') { putchar ('%'); break; } else if (*fmt == 'b') { char *p = getstr(); if (print_escape_str(p)) { return (rval); } break; } /* skip to field width */ for (; strchr(SKIP1, *fmt); ++fmt) ; if (*fmt == '*') { ++fmt; havefieldwidth = 1; fieldwidth = getint(); } else havefieldwidth = 0; /* skip to field precision */ for (; strchr(SKIP2, *fmt); ++fmt) ; haveprecision = 0; if (*fmt == '.') { ++fmt; if (*fmt == '*') { ++fmt; haveprecision = 1; precision = getint(); } for (; strchr(SKIP2, *fmt); ++fmt) ; } if (!*fmt) { warnx ("missing format character"); return(1); } convch = *fmt; nextch = *(fmt + 1); *(fmt + 1) = '\0'; switch(convch) { case 'c': { char p = getchr(); PF(start, p); break; } case 's': { char *p = getstr(); PF(start, p); break; } case 'd': case 'i': { long p; char *f = mklong(start, convch); if (!f) { warnx("out of memory"); return (1); } p = getlong(); PF(f, p); break; } case 'o': case 'u': case 'x': case 'X': { unsigned long p; char *f = mklong(start, convch); if (!f) { warnx("out of memory"); return (1); } p = getulong(); PF(f, p); break; } case 'a': case 'A': case 'e': case 'E': case 'f': case 'F': case 'g': case 'G': { double p = getdouble(); PF(start, p); break; } default: warnx ("%s: invalid directive", start); return(1); } *(fmt + 1) = nextch; break; case '\\': fmt += print_escape(fmt); break; default: putchar (*fmt); break; } } } while (gargv > argv && *gargv); return (rval); } /* * Print SysV echo(1) style escape string * Halts processing string and returns 1 if a \c escape is encountered. */ static int print_escape_str(const char *str) { int value; int c; while (*str) { if (*str == '\\') { str++; /* * %b string octal constants are not like those in C. * They start with a \0, and are followed by 0, 1, 2, * or 3 octal digits. */ if (*str == '0') { str++; for (c = 3, value = 0; c-- && isodigit(*str); str++) { value <<= 3; value += octtobin(*str); } putchar (value); str--; } else if (*str == 'c') { return 1; } else { str--; str += print_escape(str); } } else { putchar (*str); } str++; } return 0; } /* * Print "standard" escape characters */ static int print_escape(const char *str) { const char *start = str; int value; int c; str++; switch (*str) { case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': for (c = 3, value = 0; c-- && isodigit(*str); str++) { value <<= 3; value += octtobin(*str); } putchar(value); return str - start - 1; /* NOTREACHED */ case 'x': str++; for (value = 0; isxdigit((unsigned char)*str); str++) { value <<= 4; value += hextobin(*str); } if (value > UCHAR_MAX) { warnx ("escape sequence out of range for character"); rval = 1; } putchar (value); return str - start - 1; /* NOTREACHED */ case '\\': /* backslash */ putchar('\\'); break; case '\'': /* single quote */ putchar('\''); break; case '"': /* double quote */ putchar('"'); break; case 'a': /* alert */ putchar('\a'); break; case 'b': /* backspace */ putchar('\b'); break; case 'e': /* escape */ putchar(033); break; case 'f': /* form-feed */ putchar('\f'); break; case 'n': /* newline */ putchar('\n'); break; case 'r': /* carriage-return */ putchar('\r'); break; case 't': /* tab */ putchar('\t'); break; case 'v': /* vertical-tab */ putchar('\v'); break; case '\0': warnx("null escape sequence"); rval = 1; return 0; default: putchar(*str); warnx("unknown escape sequence `\\%c'", *str); rval = 1; } return 1; } static char * mklong(const char *str, int ch) { static char *copy; static int copysize; int len; len = strlen(str) + 2; if (copysize < len) { char *newcopy; copysize = len + 256; newcopy = realloc(copy, copysize); if (newcopy == NULL) { copysize = 0; free(copy); copy = NULL; return (NULL); } copy = newcopy; } (void) memmove(copy, str, len - 3); copy[len - 3] = 'l'; copy[len - 2] = ch; copy[len - 1] = '\0'; return (copy); } static int getchr(void) { if (!*gargv) return((int)'\0'); return((int)**gargv++); } static char * getstr(void) { if (!*gargv) return(""); return(*gargv++); } static char *number = "+-.0123456789"; static int getint(void) { if (!*gargv) return(0); if (strchr(number, **gargv)) return(atoi(*gargv++)); return 0; } static long getlong(void) { long val; char *ep; if (!*gargv) return(0L); if (**gargv == '\"' || **gargv == '\'') return (long) *((*gargv++)+1); errno = 0; val = strtol (*gargv, &ep, 0); check_conversion(*gargv++, ep); return val; } static unsigned long getulong(void) { unsigned long val; char *ep; if (!*gargv) return(0UL); if (**gargv == '\"' || **gargv == '\'') return (unsigned long) *((*gargv++)+1); errno = 0; val = strtoul (*gargv, &ep, 0); check_conversion(*gargv++, ep); return val; } static double getdouble(void) { double val; char *ep; if (!*gargv) return(0.0); if (**gargv == '\"' || **gargv == '\'') return (double) *((*gargv++)+1); errno = 0; val = strtod (*gargv, &ep); check_conversion(*gargv++, ep); return val; } static void check_conversion(const char *s, const char *ep) { if (*ep) { if (ep == s) warnx ("%s: expected numeric value", s); else warnx ("%s: not completely converted", s); rval = 1; } else if (errno == ERANGE) { (void)fprintf(stderr, "%s: %s\n", s, strerror(ERANGE)); rval = 1; } } static void usage(void) { (void)fprintf(stderr, "usage: printf format [argument ...]\n"); }