stdio.c revision 1.2
1/* $NetBSD: stdio.c,v 1.2 2020/08/11 13:15:37 christos Exp $ */ 2 3/* $OpenLDAP$ */ 4/* This work is part of OpenLDAP Software <http://www.openldap.org/>. 5 * 6 * Copyright 1998-2020 The OpenLDAP Foundation. 7 * All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted only as authorized by the OpenLDAP 11 * Public License. 12 * 13 * A copy of this license is available in the file LICENSE in the 14 * top-level directory of the distribution or, alternatively, at 15 * <http://www.OpenLDAP.org/license.html>. 16 */ 17 18#include <sys/cdefs.h> 19__RCSID("$NetBSD: stdio.c,v 1.2 2020/08/11 13:15:37 christos Exp $"); 20 21#include "portable.h" 22 23#include <stdio.h> 24#include <ac/stdarg.h> 25#include <ac/string.h> 26#include <ac/ctype.h> 27#include <lutil.h> 28 29#if !defined(HAVE_VSNPRINTF) && !defined(HAVE_EBCDIC) 30/* Write at most n characters to the buffer in str, return the 31 * number of chars written or -1 if the buffer would have been 32 * overflowed. 33 * 34 * This is portable to any POSIX-compliant system. We use pipe() 35 * to create a valid file descriptor, and then fdopen() it to get 36 * a valid FILE pointer. The user's buffer and size are assigned 37 * to the FILE pointer using setvbuf. Then we close the read side 38 * of the pipe to invalidate the descriptor. 39 * 40 * If the write arguments all fit into size n, the write will 41 * return successfully. If the write is too large, the stdio 42 * buffer will need to be flushed to the underlying file descriptor. 43 * The flush will fail because it is attempting to write to a 44 * broken pipe, and the write will be terminated. 45 * -- hyc, 2002-07-19 46 */ 47/* This emulation uses vfprintf; on OS/390 we're also emulating 48 * that function so it's more efficient just to have a separate 49 * version of vsnprintf there. 50 */ 51#include <ac/signal.h> 52int ber_pvt_vsnprintf( char *str, size_t n, const char *fmt, va_list ap ) 53{ 54 int fds[2], res; 55 FILE *f; 56 RETSIGTYPE (*sig)(); 57 58 if (pipe( fds )) return -1; 59 60 f = fdopen( fds[1], "w" ); 61 if ( !f ) { 62 close( fds[1] ); 63 close( fds[0] ); 64 return -1; 65 } 66 setvbuf( f, str, _IOFBF, n ); 67 sig = signal( SIGPIPE, SIG_IGN ); 68 close( fds[0] ); 69 70 res = vfprintf( f, fmt, ap ); 71 72 fclose( f ); 73 signal( SIGPIPE, sig ); 74 if ( res > 0 && res < n ) { 75 res = vsprintf( str, fmt, ap ); 76 } 77 return res; 78} 79#endif 80 81#ifndef HAVE_SNPRINTF 82int ber_pvt_snprintf( char *str, size_t n, const char *fmt, ... ) 83{ 84 va_list ap; 85 int res; 86 87 va_start( ap, fmt ); 88 res = vsnprintf( str, n, fmt, ap ); 89 va_end( ap ); 90 return res; 91} 92#endif /* !HAVE_SNPRINTF */ 93 94#ifdef HAVE_EBCDIC 95/* stdio replacements with ASCII/EBCDIC translation for OS/390. 96 * The OS/390 port depends on the CONVLIT compiler option being 97 * used to force character and string literals to be compiled in 98 * ISO8859-1, and the __LIBASCII cpp symbol to be defined to use the 99 * OS/390 ASCII-compatibility library. This library only supplies 100 * an ASCII version of sprintf, so other needed functions are 101 * provided here. 102 * 103 * All of the internal character manipulation is done in ASCII, 104 * but file I/O is EBCDIC, so we catch any stdio reading/writing 105 * of files here and do the translations. 106 */ 107 108#undef fputs 109#undef fgets 110 111char *ber_pvt_fgets( char *s, int n, FILE *fp ) 112{ 113 s = (char *)fgets( s, n, fp ); 114 if ( s ) __etoa( s ); 115 return s; 116} 117 118int ber_pvt_fputs( const char *str, FILE *fp ) 119{ 120 char buf[8192]; 121 122 strncpy( buf, str, sizeof(buf) ); 123 __atoe( buf ); 124 return fputs( buf, fp ); 125} 126 127/* The __LIBASCII doesn't include a working vsprintf, so we make do 128 * using just sprintf. This is a very simplistic parser that looks for 129 * format strings and uses sprintf to process them one at a time. 130 * Literal text is just copied straight to the destination. 131 * The result is appended to the destination string. The parser 132 * recognizes field-width specifiers and the 'l' qualifier; it 133 * may need to be extended to recognize other qualifiers but so 134 * far this seems to be enough. 135 */ 136int ber_pvt_vsnprintf( char *str, size_t n, const char *fmt, va_list ap ) 137{ 138 char *ptr, *pct, *s2, *f2, *end; 139 char fm2[64]; 140 int len, rem; 141 142 ptr = (char *)fmt; 143 s2 = str; 144 fm2[0] = '%'; 145 if (n) { 146 end = str + n; 147 } else { 148 end = NULL; 149 } 150 151 for (pct = strchr(ptr, '%'); pct; pct = strchr(ptr, '%')) { 152 len = pct-ptr; 153 if (end) { 154 rem = end-s2; 155 if (rem < 1) return -1; 156 if (rem < len) len = rem; 157 } 158 s2 = lutil_strncopy( s2, ptr, len ); 159 /* Did we cheat the length above? If so, bail out */ 160 if (len < pct-ptr) return -1; 161 for (pct++, f2 = fm2+1; isdigit(*pct);) *f2++ = *pct++; 162 if (*pct == 'l') *f2++ = *pct++; 163 if (*pct == '%') { 164 *s2++ = '%'; 165 } else { 166 *f2++ = *pct; 167 *f2 = '\0'; 168 if (*pct == 's') { 169 char *ss = va_arg(ap, char *); 170 /* Attempt to limit sprintf output. This 171 * may be thrown off if field widths were 172 * specified for this string. 173 * 174 * If it looks like the string is too 175 * long for the remaining buffer, bypass 176 * sprintf and just copy what fits, then 177 * quit. 178 */ 179 if (end && strlen(ss) > (rem=end-s2)) { 180 strncpy(s2, ss, rem); 181 return -1; 182 } else { 183 s2 += sprintf(s2, fm2, ss); 184 } 185 } else { 186 s2 += sprintf(s2, fm2, va_arg(ap, int)); 187 } 188 } 189 ptr = pct + 1; 190 } 191 if (end) { 192 rem = end-s2; 193 if (rem > 0) { 194 len = strlen(ptr); 195 s2 = lutil_strncopy( s2, ptr, rem ); 196 rem -= len; 197 } 198 if (rem < 0) return -1; 199 } else { 200 s2 = lutil_strcopy( s2, ptr ); 201 } 202 return s2 - str; 203} 204 205int ber_pvt_vsprintf( char *str, const char *fmt, va_list ap ) 206{ 207 return vsnprintf( str, 0, fmt, ap ); 208} 209 210/* The fixed buffer size here is a problem, we don't know how 211 * to flush the buffer and keep printing if the msg is too big. 212 * Hopefully we never try to write something bigger than this 213 * in a log msg... 214 */ 215int ber_pvt_vfprintf( FILE *fp, const char *fmt, va_list ap ) 216{ 217 char buf[8192]; 218 int res; 219 220 vsnprintf( buf, sizeof(buf), fmt, ap ); 221 __atoe( buf ); 222 res = fputs( buf, fp ); 223 if (res == EOF) res = -1; 224 return res; 225} 226 227int ber_pvt_printf( const char *fmt, ... ) 228{ 229 va_list ap; 230 int res; 231 232 va_start( ap, fmt ); 233 res = ber_pvt_vfprintf( stdout, fmt, ap ); 234 va_end( ap ); 235 return res; 236} 237 238int ber_pvt_fprintf( FILE *fp, const char *fmt, ... ) 239{ 240 va_list ap; 241 int res; 242 243 va_start( ap, fmt ); 244 res = ber_pvt_vfprintf( fp, fmt, ap ); 245 va_end( ap ); 246 return res; 247} 248#endif 249