/* * Copyright (c) 1997 - 2004 Kungliga Tekniska Högskolan * (Royal Institute of Technology, Stockholm, Sweden). * 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 Institute 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 INSTITUTE 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 INSTITUTE 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. */ /* snprintf.c - Formatted, length-limited print to a string */ #include #include #include #include #include #include #include #include #ifndef AFS_NT40_ENV #include #include #ifndef HAVE_VSYSLOG #include #endif #else #include #endif #if defined(AFS_AIX32_ENV) || defined(AFS_SUN_ENV) || defined(AFS_XBSD_ENV) || defined(AFS_HPUX_ENV) || defined(AFS_SGI65_ENV) #include #endif /* This is an enhanced version of the *printf functionality shipped * with Heimdal. In addition to the standard Unix formatting types * this version also supports Microsoft's I32 and I64 type modifiers * and the OpenAFS I type which is used to generate output from * network byte order IPv4 addresses (either dotted notation or * hostname lookups. Implementation details follow: * * - Actually obeys the length limit, which (unfortunately) many * implementations of snprintf do not. * * - Supports all the standard format specifiers for integers * (d, i, o, u, x, X), floating-point values (f, e, E, g, G), * and strings and characters (c, s, %), plus a few unusual * but useful ones described below. * * - The Microsoft integral size modifiers I32 and I64 are * supported. I32 is equivalent to 'l'. * I64 is equivalent to 'll'. * * - Supports all the standard flags (-, 0, +, space, #). These * flags are ignored if used when they are not appropriate. * * - Supports the standard size modifiers for short (h), long (h), * and double (L) arguments. These modifiers are ignored if used * when they are not appropriate. * * - Supports minimum field width and precision, where appropriate, * including the use of '*' to specify a value given as an argument * instead of in the format string. There is a maximum precision * of 100 digits. * * - The 'p' specifier for printing pointers is implemented using * compile time knowledge. (AFS_64BITPOINTER_ENV) * * - Floating-point specifier (%e, %f, %g) are implemented by * calling the standard sprintf, and thus may be unsafe. * * - The '%...$' notation is used primarily when the format string * is specified by the user, who knows but cannot change the order * of the arguments. Such usage is inherently dangerous and * insecure; thus, it is not supported. * * - Passing in a format and an NULL buffer is supported. This * will compute the size of the buffer required by the format * and the provided input parameters. * * The custom format specifier '%I' is supported. This specifier * takes as its argument an unsigned long integer containing an * IPv4 address in network byte order. The address is rendered * either as a hostname or as a dotted quad, as follows: * * - If precision is nonzero or unspecified, a hostname lookup * is attempted; if it is successful, the hostname is printed. * If the hostname lookup fails, the address is printed in * dotted-quad notation. * * - If precision is explicitly specified as 0, then the hostname * lookup is skipped, and dotted-quad notation is always used. * * - If a hostname is to be printed: * + The precision controls the maximum number of characters * printed, as with %s. * + If the '#' flag is specified, any letters in the hostname * will be forced to lower case before printing. * + If the '+' flag is specified, any letters in the hostname * will be forced to upper case before printing. If both * '#' and '+' are given, the '+' flag will be ignored. * + The '0' and ' ' flags have no effect. * * - If a dotted quad is to be printed: * + The precision has no effect; dotted quads are always * 7 to 12 characters in length, depending on the value * to be printed and the format flags used. * + If the '0' flag is given, each field (byte) of the address * will be padded with '0' on the left to three digits. * + If the ' ' flag is given, each field (byte) of the address * will be padded with spaces on the left to three digits. If * both '0' and ' ' are given, the ' ' flag will be ignored. * + The '#' and '+' flags have no effect. * * A test program exists in src/util/tests/snprintf_tests.c. */ #define MAXPREC 100 enum format_flags { minus_flag = 1, plus_flag = 2, space_flag = 4, alternate_flag = 8, zero_flag = 16 }; /* * Common state */ struct snprintf_state { unsigned char *str; unsigned char *s; unsigned char *theend; size_t sz; size_t max_sz; void (*append_char)(struct snprintf_state *, unsigned char); /* XXX - methods */ }; static int afs_sn_reserve (struct snprintf_state *state, size_t n) { return state->s + n > state->theend; } static void afs_sn_append_char (struct snprintf_state *state, unsigned char c) { if (!afs_sn_reserve (state, 1)) *state->s++ = c; } static int as_reserve (struct snprintf_state *state, size_t n) { if (state->s + n > state->theend) { size_t off = state->s - state->str; unsigned char *tmp; if (state->max_sz && state->sz >= state->max_sz) return 1; state->sz = max(state->sz * 2, state->sz + n); if (state->max_sz) state->sz = min(state->sz, state->max_sz); tmp = (unsigned char *)realloc (state->str, state->sz); if (tmp == NULL) return 1; state->str = tmp; state->s = state->str + off; state->theend = state->str + state->sz - 1; } return 0; } static void as_append_char (struct snprintf_state *state, unsigned char c) { if(!as_reserve (state, 1)) *state->s++ = c; } /* longest integer types */ #ifdef AFS_64BIT_ENV typedef afs_uint64 u_longest; typedef afs_int64 longest; #else typedef afs_uint32 u_longest; typedef afs_int32 longest; #endif static int pad(struct snprintf_state *state, int width, char c) { int len = 0; while(width-- > 0){ (*state->append_char)(state, c); ++len; } return len; } /* return true if we should use alternatve hex form */ static int use_alternative (int flags, u_longest num, unsigned base) { return (flags & alternate_flag) && base == 16 && num != 0; } static int append_number(struct snprintf_state *state, u_longest num, unsigned base, const char *rep, int width, int prec, int flags, int minusp) { int len = 0; u_longest n = num; char nstr[MAXPREC]; /* enough for <192 bit octal integers */ int nstart, nlen; char signchar; /* given precision, ignore zero flag */ if(prec != -1) flags &= ~zero_flag; else prec = 1; /* format number as string */ nstart = sizeof(nstr); nlen = 0; nstr[--nstart] = '\0'; do { nstr[--nstart] = rep[n % base]; ++nlen; n /= base; } while(n); /* zero value with zero precision should produce no digits */ if(prec == 0 && num == 0) { nlen--; nstart++; } /* figure out what char to use for sign */ if(minusp) signchar = '-'; else if((flags & plus_flag)) signchar = '+'; else if((flags & space_flag)) signchar = ' '; else signchar = '\0'; if((flags & alternate_flag) && base == 8) { /* if necessary, increase the precision to make first digit a zero */ /* XXX C99 claims (regarding # and %o) that "if the value and precision are both 0, a single 0 is printed", but there is no such wording for %x. This would mean that %#.o would output "0", but %#.x "". This does not make sense, and is also not what other printf implementations are doing. */ if(prec <= nlen && nstr[nstart] != '0' && nstr[nstart] != '\0') prec = nlen + 1; } /* possible formats: pad | sign | alt | zero | digits sign | alt | zero | digits | pad minus_flag sign | alt | zero | digits zero_flag */ /* if not right justifying or padding with zeros, we need to compute the length of the rest of the string, and then pad with spaces */ if(!(flags & (minus_flag | zero_flag))) { if(prec > nlen) width -= prec; else width -= nlen; if(use_alternative(flags, num, base)) width -= 2; if(signchar != '\0') width--; /* pad to width */ len += pad(state, width, ' '); } if(signchar != '\0') { (*state->append_char)(state, signchar); ++len; } if(use_alternative(flags, num, base)) { (*state->append_char)(state, '0'); (*state->append_char)(state, rep[10] + 23); /* XXX */ len += 2; } if(flags & zero_flag) { /* pad to width with zeros */ if(prec - nlen > width - len - nlen) len += pad(state, prec - nlen, '0'); else len += pad(state, width - len - nlen, '0'); } else /* pad to prec with zeros */ len += pad(state, prec - nlen, '0'); while(nstr[nstart] != '\0') { (*state->append_char)(state, nstr[nstart++]); ++len; } if(flags & minus_flag) len += pad(state, width - len, ' '); return len; } /* * return length */ static int append_string (struct snprintf_state *state, const unsigned char *arg, int width, int prec, int flags) { int len = 0; if(arg == NULL) arg = (const unsigned char*)"(null)"; if(prec != -1) width -= prec; else width -= (int)strlen((const char *)arg); if(!(flags & minus_flag)) len += pad(state, width, ' '); if (prec != -1) { while (*arg && prec--) { (*state->append_char) (state, *arg++); ++len; } } else { while (*arg) { (*state->append_char) (state, *arg++); ++len; } } if(flags & minus_flag) len += pad(state, width, ' '); return len; } static int append_char(struct snprintf_state *state, unsigned char arg, int width, int flags) { int len = 0; while(!(flags & minus_flag) && --width > 0) { (*state->append_char) (state, ' ') ; ++len; } (*state->append_char) (state, arg); ++len; while((flags & minus_flag) && --width > 0) { (*state->append_char) (state, ' '); ++len; } return 0; } #define MAXPREC 100 static int append_float(struct snprintf_state *state, char type, double arg, int width, int prec, int flags) { int len = 0; char fbuf[20], xbuf[MAXPREC + 21]; sprintf(fbuf, "%%%s%s.*L%c", (flags & plus_flag) ? "+" : ((flags & space_flag) ? " " : ((flags & minus_flag) ? "-" : "")), (flags & alternate_flag) ? "#" : "", type); if (prec == -1) prec = 6; if (prec > MAXPREC) prec = MAXPREC; sprintf(xbuf, fbuf, prec, arg); len = append_string(state, (unsigned char *)xbuf, width, -1, 0); return len; } static int append_address(struct snprintf_state *state, afs_uint32 arg, int width, int prec, int flags) { int len = 0; struct hostent * he; struct in_addr ia; char * x, *y; /* IP address: * value is provided as a network-order unsigned long integer * precision specifies max hostname length, as for %s * if precision is explicitly 0, no hostname lookup is done * if 0fill specified, IPaddr fields are 0-filled to 3 digits * if spsign specified, IPaddr fields are space-filled to 3 digits */ ia.s_addr = arg; if (prec == 0) he = 0; else he = gethostbyaddr((char *)&ia, 4, AF_INET); if (he) { x = he->h_name; len = (int)strlen(x); if (prec != -1 && prec < len) width = prec; else width = len; if (flags & alternate_flag) { for (y = x; *y; y++) if (isupper(*y)) *y = tolower(*y); } else if (flags & plus_flag) { for (y = x; *y; y++) if (islower(*y)) *y = toupper(*y); } len = append_string(state, (unsigned char *)x, width, prec, 0); } else { char xbuf[16]; arg = ntohl(arg); if (flags & zero_flag) { x = "%03u.%03u.%03u.%03u"; } else if (flags & space_flag) { x = "%3u.%3u.%3u.%3u"; } else { x = "%u.%u.%u.%u"; } /* typecast to whatever '%u' is! */ sprintf(xbuf, x, (unsigned int)((arg & 0xff000000) >> 24), (unsigned int)((arg & 0x00ff0000) >> 16), (unsigned int)((arg & 0x0000ff00) >> 8), (unsigned int)(arg & 0x000000ff)); len = append_string(state, (unsigned char *)xbuf, 0, -1, 0); } return len; } /* * This can't be made into a function... */ #if defined(AFS_64BIT_ENV) #if defined(AFS_NT40_ENV) #define PARSE_INT_FORMAT(res, arg, unsig) \ if (long_long_flag) \ res = (unsig __int64)va_arg(arg, unsig __int64); \ else if (long_flag || addr_flag) \ res = (unsig long)va_arg(arg, unsig long); \ else if (size_t_flag) \ res = (size_t)va_arg(arg, size_t); \ else if (short_flag) \ res = (unsig short)va_arg(arg, unsig int); \ else \ res = (unsig int)va_arg(arg, unsig int) #else /* AFS_NT40_ENV */ #define PARSE_INT_FORMAT(res, arg, unsig) \ if (long_long_flag) \ res = (unsig long long)va_arg(arg, unsig long long); \ else if (long_flag || addr_flag) \ res = (unsig long)va_arg(arg, unsig long); \ else if (size_t_flag) \ res = (size_t)va_arg(arg, size_t); \ else if (short_flag) \ res = (unsig short)va_arg(arg, unsig int); \ else \ res = (unsig int)va_arg(arg, unsig int) #endif #else #define PARSE_INT_FORMAT(res, arg, unsig) \ if (long_flag || addr_flag) \ res = (afs_uint32)va_arg(arg, afs_uint32); \ else if (size_t_flag) \ res = (size_t)va_arg(arg, size_t); \ else if (short_flag) \ res = (unsig short)va_arg(arg, unsig int); \ else \ res = (unsig int)va_arg(arg, unsig int) #endif /* * zyxprintf - return length, as snprintf */ static int xyzprintf (struct snprintf_state *state, const char *char_format, va_list ap) { const unsigned char *format = (const unsigned char *)char_format; unsigned char c; int len = 0; while((c = *format++)) { if (c == '%') { int flags = 0; int width = 0; int prec = -1; int size_t_flag = 0; int long_long_flag = 0; int long_flag = 0; int short_flag = 0; int addr_flag = 0; /* flags */ while((c = *format++)){ if(c == '-') flags |= minus_flag; else if(c == '+') flags |= plus_flag; else if(c == ' ') flags |= space_flag; else if(c == '#') flags |= alternate_flag; else if(c == '0') flags |= zero_flag; else if(c == '\'') ; /* just ignore */ else break; } if((flags & space_flag) && (flags & plus_flag)) flags ^= space_flag; if((flags & minus_flag) && (flags & zero_flag)) flags ^= zero_flag; /* width */ if (isdigit(c)) do { width = width * 10 + c - '0'; c = *format++; } while(isdigit(c)); else if(c == '*') { width = va_arg(ap, int); c = *format++; } /* precision */ if (c == '.') { prec = 0; c = *format++; if (isdigit(c)) do { prec = prec * 10 + c - '0'; c = *format++; } while(isdigit(c)); else if (c == '*') { prec = va_arg(ap, int); c = *format++; } } /* size */ if (c == 'h') { short_flag = 1; c = *format++; } else if (c == 'z') { size_t_flag = 1; c = *format++; } else if (c == 'l') { long_flag = 1; c = *format++; if (c == 'l') { long_long_flag = 1; c = *format++; } } else if (c == 'I') { /* This could be either Microsoft I{32,64} notation */ c = *format++; if (c == '3') { long_flag = 1; c = *format++; if (c == '2') { c = *format++; } } else if (c == '6') { long_flag = 1; c = *format++; if (c == '4') { long_long_flag = 1; c = *format++; } } else { /* Or the OpenAFS special %I meaning network address */ addr_flag = 1; --format; c = 'I'; } } else if (c == 'p') { flags |= zero_flag; if (prec == -1) prec = 2 * sizeof(void *); if (sizeof(void *) == sizeof(afs_uint64)) long_long_flag = 1; else if (sizeof(void *) == sizeof(afs_uint32)) long_flag = 1; else long_flag = 1; } if(c != 'd' && c != 'i' && c != 'I') flags &= ~(plus_flag | space_flag); switch (c) { case 'c' : append_char(state, va_arg(ap, int), width, flags); ++len; break; case 's' : len += append_string(state, va_arg(ap, unsigned char*), width, prec, flags); break; case 'd' : case 'i' : { longest arg; u_longest num; int minusp = 0; PARSE_INT_FORMAT(arg, ap, signed); if (arg < 0) { minusp = 1; num = -arg; } else num = arg; len += append_number (state, num, 10, "0123456789", width, prec, flags, minusp); break; } case 'u' : { u_longest arg; PARSE_INT_FORMAT(arg, ap, unsigned); len += append_number (state, arg, 10, "0123456789", width, prec, flags, 0); break; } case 'o' : { u_longest arg; PARSE_INT_FORMAT(arg, ap, unsigned); len += append_number (state, arg, 010, "01234567", width, prec, flags, 0); break; } case 'x' : { u_longest arg; PARSE_INT_FORMAT(arg, ap, unsigned); len += append_number (state, arg, 0x10, "0123456789abcdef", width, prec, flags, 0); break; } case 'X' :{ u_longest arg; PARSE_INT_FORMAT(arg, ap, unsigned); len += append_number (state, arg, 0x10, "0123456789ABCDEF", width, prec, flags, 0); break; } case 'p' : { #ifdef AFS_64BITPOINTER_ENV u_longest arg = (u_longest)va_arg(ap, void*); #else u_longest arg = (unsigned long)va_arg(ap, void*); #endif len += append_number (state, arg, 0x10, "0123456789ABCDEF", width, prec, flags, 0); break; } case 'n' : { int *arg = va_arg(ap, int*); *arg = (int)(state->s - state->str); break; } case 'I' : { u_longest arg; PARSE_INT_FORMAT(arg, ap, unsigned); len += append_address (state, (unsigned long)arg, width, prec, flags); break; } case 'e': case 'E': case 'f': case 'g': case 'G': { double arg = (double)va_arg(ap, double); len += append_float (state, c, arg, width, prec, flags); break; } case '\0' : --format; /* FALLTHROUGH */ case '%' : (*state->append_char)(state, c); ++len; break; default : (*state->append_char)(state, '%'); (*state->append_char)(state, c); len += 2; break; } } else { (*state->append_char) (state, c); ++len; } } return len; } int afs_vsnprintf (char *str, size_t sz, const char *format, va_list args) { struct snprintf_state state; int ret; unsigned char *ustr = (unsigned char *)str; state.max_sz = 0; state.sz = sz; state.str = ustr; state.s = ustr; state.theend = ustr + sz - (sz > 0); state.append_char = afs_sn_append_char; ret = xyzprintf (&state, format, args); if (state.s != NULL && sz != 0) *state.s = '\0'; return ret; } int afs_snprintf (char *str, size_t sz, const char *format, ...) { va_list args; int ret; va_start(args, format); ret = afs_vsnprintf (str, sz, format, args); va_end(args); #ifdef PARANOIA { int ret2; unsigned char *tmp; tmp = (unsigned char *)malloc (sz); if (tmp == NULL) abort (); va_start(args, format); ret2 = afs_vsprintf (tmp, format, args); va_end(args); if (ret != ret2 || strcmp(str, tmp)) abort (); free (tmp); } #endif return ret; } int afs_vasnprintf (char **ret, size_t max_sz, const char *format, va_list args) { int st; struct snprintf_state state; state.max_sz = max_sz; state.sz = 1; state.str = (unsigned char *)malloc(state.sz); if (state.str == NULL) { *ret = NULL; return -1; } state.s = state.str; state.theend = state.s + state.sz - 1; state.append_char = as_append_char; st = xyzprintf (&state, format, args); if (st > state.sz) { free (state.str); *ret = NULL; return -1; } else { char *tmp; *state.s = '\0'; tmp = (char *)realloc (state.str, st+1); if (tmp == NULL) { free (state.str); *ret = NULL; return -1; } *ret = tmp; return st; } } int afs_vasprintf (char **ret, const char *format, va_list args) { return afs_vasnprintf (ret, 0, format, args); } int afs_asprintf (char **ret, const char *format, ...) { va_list args; int val; va_start(args, format); val = afs_vasprintf (ret, format, args); va_end(args); #ifdef PARANOIA { int ret2; unsigned char *tmp; tmp = (unsigned char *)malloc (val + 1); if (tmp == NULL) abort (); va_start(args, format); ret2 = afs_vsprintf (tmp, format, args); va_end(args); if (val != ret2 || strcmp(*ret, tmp)) abort (); free (tmp); } #endif return val; } int afs_asnprintf (char **ret, size_t max_sz, const char *format, ...) { va_list args; int val; va_start(args, format); val = afs_vasnprintf (ret, max_sz, format, args); #ifdef PARANOIA { int ret2; unsigned char *tmp; tmp = (unsigned char *)malloc (val + 1); if (tmp == NULL) abort (); ret2 = afs_vsprintf (tmp, format, args); if (val != ret2 || strcmp(*ret, tmp)) abort (); free (tmp); } #endif va_end(args); return val; } #if defined(AFS_OSF20_ENV) && !defined(AFS_DUX50_ENV) || defined(AFS_AIX32_ENV) || (defined(AFS_SUN55_ENV) && !defined(AFS_SUN56_ENV)) || !defined(HAVE_VSNPRINTF) || defined(TEST_SNPRINTF) #if defined(AFS_AIX51_ENV) || defined(AFS_NT40_ENV) int vsnprintf(char *p, size_t avail, const char *fmt, va_list ap) #else void vsnprintf(char *p, unsigned int avail, char *fmt, va_list ap) #endif { int result; result = afs_vsnprintf(p, avail, fmt, ap); #if defined(AFS_AIX51_ENV) || defined(AFS_NT40_ENV) return result; #endif } #endif /* AFS_OSF20_ENV || AFS_AIX32_ENV */ #ifndef AFS_NT40_ENV #ifndef HAVE_VSYSLOG void vsyslog(int priority, const char *format, va_list args) { char buf[1024]; afs_vsnprintf(buf, sizeof(buf), format, args); syslog(priority, "%s", buf); } #endif #if defined(AFS_OSF20_ENV) && !defined(AFS_DUX50_ENV) || defined(AFS_AIX32_ENV) || (defined(AFS_SUN55_ENV) && !defined(AFS_SUN56_ENV)) || !defined(HAVE_SNPRINTF) #ifdef AFS_AIX51_ENV int snprintf(char *p, size_t avail, const char *fmt, ...) #else void snprintf(char *p, unsigned int avail, char *fmt, ...) #endif { va_list ap; int result; va_start(ap, fmt); result = afs_vsnprintf(p, avail, fmt, ap); va_end(ap); #ifdef AFS_AIX51_ENV return result; #endif } #endif /* AFS_OSF20_ENV || AFS_AIX32_ENV */ #endif /* AFS_NT40_ENV */