/* $NiH: snprintf.c,v 1.3 2002/05/13 16:51:22 wiz Exp $ This file provides replacements for the following library functions: snprintf vsnprintf vasprintf */ /************************************************************** * Original: * Patrick Powell Tue Apr 11 09:48:21 PDT 1995 * A bombproof version of doprnt (dopr) included. * Sigh. This sort of thing is always nasty do deal with. Note that * the version here does not include floating point... * * snprintf() is used instead of sprintf() as it does limit checks * for string length. This covers a nasty loophole. * * The other functions are there to prevent NULL pointers from * causing nast effects. * * More Recently: * Brandon Long 9/15/96 for mutt 0.43 * This was ugly. It is still ugly. I opted out of floating point * numbers, but the formatter understands just about everything * from the normal C string format, at least as far as I can tell from * the Solaris 2.5 printf(3S) man page. * * Brandon Long 10/22/97 for mutt 0.87.1 * Ok, added some minimal floating point support, which means this * probably requires libm on most operating systems. Don't yet * support the exponent (e,E) and sigfig (g,G). Also, fmtint() * was pretty badly broken, it just wasn't being exercised in ways * which showed it, so that's been fixed. Also, formated the code * to mutt conventions, and removed dead code left over from the * original. Also, there is now a builtin-test, just compile with: * gcc -DTEST_SNPRINTF -o snprintf snprintf.c -lm * and run snprintf for results. * * Thomas Roessler 01/27/98 for mutt 0.89i * The PGP code was using unsigned hexadecimal formats. * Unfortunately, unsigned formats simply didn't work. * * Michael Elkins 03/05/98 for mutt 0.90.8 * The original code assumed that both snprintf() and vsnprintf() were * missing. Some systems only have snprintf() but not vsnprintf(), so * the code is now broken down under HAVE_SNPRINTF and HAVE_VSNPRINTF. * * Dieter Baron 04/16/02 for cg 0.4 * Add vasprintf front end, and the ability to resize the buffer on * demand. Make the test program compilable on systems that provide * snprintf, and add string format tests. **************************************************************/ #include "config.h" #if !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF) || !defined(HAVE_VASPRINTF) || defined(TEST_SNPRINTF) #include #include #include #include /* varargs declarations: */ #if defined(HAVE_STDARG_H) # include # define HAVE_STDARGS /* let's hope that works everywhere (mj) */ # define VA_LOCAL_DECL va_list ap # define VA_START(f) va_start(ap, f) # define VA_SHIFT(v,t) ; /* no-op for ANSI */ # define VA_END va_end(ap) #else # include # undef HAVE_STDARGS # define VA_LOCAL_DECL va_list ap # define VA_START(f) va_start(ap) /* f is ignored! */ # define VA_SHIFT(v,t) v = va_arg(ap,t) # define VA_END va_end(ap) #endif /*int snprintf (char *str, size_t count, const char *fmt, ...);*/ /*int vsnprintf (char *str, size_t count, const char *fmt, va_list arg);*/ /*int vasprintf (char **strp, const char *fmt, va_list arg);*/ struct buf { char *buffer; /* the actual buffer */ size_t maxlen; /* size of the buffer */ size_t currlen; /* length of used portion */ int resize; /* whether to resize buffer on overrun */ }; static int buf_grow(struct buf *buf); static void dopr (struct buf *buf, const char *format, va_list args); static void dopr_outch (struct buf *buf, char c); static void fmtfp (struct buf *buf, long double fvalue, int min, int max, int flags); static void fmtint (struct buf *buf, long value, int base, int min, int max, int flags); static void fmtstr (struct buf *buf, char *value, int flags, int min, int max); /* * dopr(): poor man's version of doprintf */ /* format read states */ #define DP_S_DEFAULT 0 #define DP_S_FLAGS 1 #define DP_S_MIN 2 #define DP_S_DOT 3 #define DP_S_MAX 4 #define DP_S_MOD 5 #define DP_S_CONV 6 #define DP_S_DONE 7 /* format flags - Bits */ #define DP_F_MINUS (1 << 0) #define DP_F_PLUS (1 << 1) #define DP_F_SPACE (1 << 2) #define DP_F_NUM (1 << 3) #define DP_F_ZERO (1 << 4) #define DP_F_UP (1 << 5) #define DP_F_UNSIGNED (1 << 6) /* Conversion Flags */ #define DP_C_SHORT 1 #define DP_C_LONG 2 #define DP_C_LDOUBLE 3 #define char_to_int(p) (p - '0') #define MAXX(p,q) (((p) >= (q)) ? (p) : (q)) static void dopr(struct buf *buf, const char *format, va_list args) { char ch; long value; long double fvalue; char *strvalue; int min; int max; int state; int flags; int cflags; state = DP_S_DEFAULT; flags = cflags = min = 0; buf->currlen = 0; max = -1; ch = *format++; while (state != DP_S_DONE) { if ((ch == '\0') || (buf->currlen >= buf->maxlen && !buf->resize)) state = DP_S_DONE; switch(state) { case DP_S_DEFAULT: if (ch == '%') state = DP_S_FLAGS; else dopr_outch (buf, ch); ch = *format++; break; case DP_S_FLAGS: switch (ch) { case '-': flags |= DP_F_MINUS; ch = *format++; break; case '+': flags |= DP_F_PLUS; ch = *format++; break; case ' ': flags |= DP_F_SPACE; ch = *format++; break; case '#': flags |= DP_F_NUM; ch = *format++; break; case '0': flags |= DP_F_ZERO; ch = *format++; break; default: state = DP_S_MIN; break; } break; case DP_S_MIN: if (isdigit((unsigned char)ch)) { min = 10*min + char_to_int (ch); ch = *format++; } else if (ch == '*') { min = va_arg (args, int); ch = *format++; state = DP_S_DOT; } else state = DP_S_DOT; break; case DP_S_DOT: if (ch == '.') { state = DP_S_MAX; ch = *format++; } else state = DP_S_MOD; break; case DP_S_MAX: if (isdigit((unsigned char)ch)) { if (max < 0) max = 0; max = 10*max + char_to_int (ch); ch = *format++; } else if (ch == '*') { max = va_arg (args, int); ch = *format++; state = DP_S_MOD; } else state = DP_S_MOD; break; case DP_S_MOD: /* Currently, we don't support Long Long, bummer */ switch (ch) { case 'h': cflags = DP_C_SHORT; ch = *format++; break; case 'l': cflags = DP_C_LONG; ch = *format++; break; case 'L': cflags = DP_C_LDOUBLE; ch = *format++; break; default: break; } state = DP_S_CONV; break; case DP_S_CONV: switch (ch) { case 'd': case 'i': if (cflags == DP_C_SHORT) value = va_arg (args, short int); else if (cflags == DP_C_LONG) value = va_arg (args, long int); else value = va_arg (args, int); fmtint (buf, value, 10, min, max, flags); break; case 'o': flags |= DP_F_UNSIGNED; if (cflags == DP_C_SHORT) value = va_arg (args, unsigned short int); else if (cflags == DP_C_LONG) value = va_arg (args, unsigned long int); else value = va_arg (args, unsigned int); fmtint (buf, value, 8, min, max, flags); break; case 'u': flags |= DP_F_UNSIGNED; if (cflags == DP_C_SHORT) value = va_arg (args, unsigned short int); else if (cflags == DP_C_LONG) value = va_arg (args, unsigned long int); else value = va_arg (args, unsigned int); fmtint (buf, value, 10, min, max, flags); break; case 'X': flags |= DP_F_UP; case 'x': flags |= DP_F_UNSIGNED; if (cflags == DP_C_SHORT) value = va_arg (args, unsigned short int); else if (cflags == DP_C_LONG) value = va_arg (args, unsigned long int); else value = va_arg (args, unsigned int); fmtint (buf, value, 16, min, max, flags); break; case 'f': if (cflags == DP_C_LDOUBLE) fvalue = va_arg (args, long double); else fvalue = va_arg (args, double); /* um, floating point? */ fmtfp (buf, fvalue, min, max, flags); break; case 'E': flags |= DP_F_UP; case 'e': if (cflags == DP_C_LDOUBLE) fvalue = va_arg (args, long double); else fvalue = va_arg (args, double); break; case 'G': flags |= DP_F_UP; case 'g': if (cflags == DP_C_LDOUBLE) fvalue = va_arg (args, long double); else fvalue = va_arg (args, double); break; case 'c': dopr_outch (buf, va_arg (args, int)); break; case 's': strvalue = va_arg (args, char *); fmtstr (buf, strvalue, flags, min, max); break; case 'p': strvalue = va_arg (args, void *); fmtint (buf, (long) strvalue, 16, min, max, flags); break; case 'n': if (cflags == DP_C_SHORT) { short int *num; num = va_arg (args, short int *); *num = buf->currlen; } else if (cflags == DP_C_LONG) { long int *num; num = va_arg (args, long int *); *num = buf->currlen; } else { int *num; num = va_arg (args, int *); *num = buf->currlen; } break; case '%': dopr_outch (buf, ch); break; case 'w': /* not supported yet, treat as next char */ ch = *format++; break; default: /* Unknown, skip */ break; } ch = *format++; state = DP_S_DEFAULT; flags = cflags = min = 0; max = -1; break; case DP_S_DONE: break; default: /* hmm? */ break; /* some picky compilers need this */ } } if (buf->currlen >= buf->maxlen) { if (buf->resize) { if (buf_grow(buf) < 0) return; } else buf->buffer[buf->maxlen-1] = '\0'; } else buf->buffer[buf->currlen] = '\0'; } static void fmtstr(struct buf *buf, char *value, int flags, int min, int max) { int padlen; /* amount to pad */ int cnt; if (value == 0) { value = "(null)"; } cnt = 0; padlen = min - strlen(value); if (padlen < 0) padlen = 0; if (flags & DP_F_MINUS) padlen = -padlen; /* Left Justify */ while ((padlen > 0) && (max < 0 || cnt < max)) { dopr_outch (buf, ' '); --padlen; ++cnt; } while (*value && (max < 0 || cnt < max)) { dopr_outch (buf, *value++); ++cnt; } while ((padlen < 0) && (max < 0 || cnt < max)) { dopr_outch (buf, ' '); ++padlen; ++cnt; } } /* Have to handle DP_F_NUM (ie 0x and 0 alternates) */ static void fmtint(struct buf *buf, long value, int base, int min, int max, int flags) { int signvalue = 0; unsigned long uvalue; char convert[20]; int place = 0; int spadlen = 0; /* amount to space pad */ int zpadlen = 0; /* amount to zero pad */ int caps = 0; if (max < 0) max = 0; uvalue = value; if(!(flags & DP_F_UNSIGNED)) { if( value < 0 ) { signvalue = '-'; uvalue = -value; } else if (flags & DP_F_PLUS) /* Do a sign (+/i) */ signvalue = '+'; else if (flags & DP_F_SPACE) signvalue = ' '; } if (flags & DP_F_UP) caps = 1; /* Should characters be upper case? */ do { convert[place++] = (caps? "0123456789ABCDEF":"0123456789abcdef") [uvalue % (unsigned)base ]; uvalue = (uvalue / (unsigned)base ); } while(uvalue && (place < 20)); if (place == 20) place--; convert[place] = 0; zpadlen = max - place; spadlen = min - MAXX(max, place) - (signvalue ? 1 : 0); if (zpadlen < 0) zpadlen = 0; if (spadlen < 0) spadlen = 0; if (flags & DP_F_ZERO) { zpadlen = MAXX(zpadlen, spadlen); spadlen = 0; } if (flags & DP_F_MINUS) spadlen = -spadlen; /* Left Justifty */ #ifdef DEBUG_SNPRINTF dprint (1, (debugfile, "zpad: %d, spad: %d, min: %d, max: %d, place: %d\n", zpadlen, spadlen, min, max, place)); #endif /* Spaces */ while (spadlen > 0) { dopr_outch (buf, ' '); --spadlen; } /* Sign */ if (signvalue) dopr_outch (buf, signvalue); /* Zeros */ if (zpadlen > 0) { while (zpadlen > 0) { dopr_outch (buf, '0'); --zpadlen; } } /* Digits */ while (place > 0) dopr_outch (buf, convert[--place]); /* Left Justified spaces */ while (spadlen < 0) { dopr_outch (buf, ' '); ++spadlen; } } static long double abs_val(long double value) { long double result = value; if (value < 0) result = -value; return result; } static long double pow10(int exp) { long double result = 1; while (exp) { result *= 10; exp--; } return result; } static long round(long double value) { long intpart; intpart = value; value = value - intpart; if (value >= 0.5) intpart++; return intpart; } static void fmtfp(struct buf *buf, long double fvalue, int min, int max, int flags) { int signvalue = 0; long double ufvalue; char iconvert[20]; char fconvert[20]; int iplace = 0; int fplace = 0; int padlen = 0; /* amount to pad */ int zpadlen = 0; int caps = 0; long intpart; long fracpart; /* * AIX manpage says the default is 0, but Solaris says the default * is 6, and sprintf on AIX defaults to 6 */ if (max < 0) max = 6; ufvalue = abs_val (fvalue); if (fvalue < 0) signvalue = '-'; else if (flags & DP_F_PLUS) /* Do a sign (+/i) */ signvalue = '+'; else if (flags & DP_F_SPACE) signvalue = ' '; #if 0 if (flags & DP_F_UP) caps = 1; /* Should characters be upper case? */ #endif intpart = ufvalue; /* * Sorry, we only support 9 digits past the decimal because of our * conversion method */ if (max > 9) max = 9; /* We "cheat" by converting the fractional part to integer by * multiplying by a factor of 10 */ fracpart = round ((pow10 (max)) * (ufvalue - intpart)); if (fracpart >= pow10 (max)) { intpart++; fracpart -= pow10 (max); } #ifdef DEBUG_SNPRINTF dprint (1, (debugfile, "fmtfp: %f =? %d.%d\n", fvalue, intpart, fracpart)); #endif /* Convert integer part */ do { iconvert[iplace++] = (caps? "0123456789ABCDEF":"0123456789abcdef")[intpart % 10]; intpart = (intpart / 10); } while(intpart && (iplace < 20)); if (iplace == 20) iplace--; iconvert[iplace] = 0; /* Convert fractional part */ do { fconvert[fplace++] = (caps? "0123456789ABCDEF":"0123456789abcdef")[fracpart % 10]; fracpart = (fracpart / 10); } while(fracpart && (fplace < 20)); if (fplace == 20) fplace--; fconvert[fplace] = 0; /* -1 for decimal point, another -1 if we are printing a sign */ padlen = min - iplace - max - 1 - ((signvalue) ? 1 : 0); zpadlen = max - fplace; if (zpadlen < 0) zpadlen = 0; if (padlen < 0) padlen = 0; if (flags & DP_F_MINUS) padlen = -padlen; /* Left Justifty */ if ((flags & DP_F_ZERO) && (padlen > 0)) { if (signvalue) { dopr_outch (buf, signvalue); --padlen; signvalue = 0; } while (padlen > 0) { dopr_outch (buf, '0'); --padlen; } } while (padlen > 0) { dopr_outch (buf, ' '); --padlen; } if (signvalue) dopr_outch (buf, signvalue); while (iplace > 0) dopr_outch (buf, iconvert[--iplace]); /* * Decimal point. This should probably use locale to find the correct * char to print out. */ dopr_outch (buf, '.'); while (fplace > 0) dopr_outch (buf, fconvert[--fplace]); while (zpadlen > 0) { dopr_outch (buf, '0'); --zpadlen; } while (padlen < 0) { dopr_outch (buf, ' '); ++padlen; } } static void dopr_outch (struct buf *buf, char c) { if (buf->currlen >= buf->maxlen) { if (buf->resize) { if (buf_grow(buf) < 0) return; } else return; } buf->buffer[buf->currlen++] = c; } static int buf_grow(struct buf *buf) { if (buf->buffer == NULL) { buf->buffer = malloc(64); buf->maxlen = 64; } else { buf->maxlen *= 2; buf->buffer = realloc(buf->buffer, buf->maxlen); } if (buf->buffer == NULL) { buf->resize = 0; buf->maxlen = -1; return -1; } return 0; } #endif /* !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF) */ #ifndef HAVE_VASPRINTF int vasprintf (char **strp, const char *fmt, va_list args) { struct buf buf; buf.buffer = NULL; buf.maxlen = 0; buf.resize = 1; dopr(&buf, fmt, args); *strp = buf.buffer; if (buf.buffer == NULL) return -1; return(strlen(buf.buffer)); } #endif #if !defined(HAVE_VSNPRINTF) || defined(TEST_SNPRINTF) #if defined(TEST_SNPRINTF) #define vsnprintf my_vsnprintf #endif int vsnprintf(char *str, size_t count, const char *fmt, va_list args) { struct buf buf; str[0] = 0; buf.buffer = str; buf.maxlen = count; buf.resize = 0; dopr(&buf, fmt, args); return(strlen(str)); } #endif /* !HAVE_VSNPRINTF || TEST_SNPRINTF */ #if !defined(HAVE_SNPRINTF) || defined(TEST_SNPRINTF) #if defined(TEST_SNPRINTF) #define snprintf my_snprintf #define vsnprintf my_vsnprintf #endif /* VARARGS3 */ #ifdef HAVE_STDARGS int snprintf (char *str,size_t count,const char *fmt,...) #else int snprintf (va_alist) va_dcl #endif { #ifndef HAVE_STDARGS char *str; size_t count; char *fmt; #endif VA_LOCAL_DECL; VA_START (fmt); VA_SHIFT (str, char *); VA_SHIFT (count, size_t ); VA_SHIFT (fmt, char *); (void) vsnprintf(str, count, fmt, ap); VA_END; return(strlen(str)); } #if defined(TEST_SNPRINTF) #undef snprintf #undef vsnprintf #endif #endif /* !HAVE_SNPRINTF || TEST_SNPRINTF */ #ifdef TEST_SNPRINTF #ifndef LONG_STRING #define LONG_STRING 1024 #endif int main (void) { char buf1[LONG_STRING]; char buf2[LONG_STRING]; char *fp_fmt[] = { "%-1.5f", "%1.5f", "%123.9f", "%10.5f", "% 10.5f", "%+22.9f", "%+4.9f", "%01.3f", "%4f", "%3.1f", "%3.2f", NULL }; double fp_nums[] = { -1.5, 134.21, 91340.2, 341.1234, 0203.9, 0.96, 0.996, 0.9996, 1.996, 4.136, 0}; char *int_fmt[] = { "%-1.5d", "%1.5d", "%123.9d", "%5.5d", "%10.5d", "% 10.5d", "%+22.33d", "%01.3d", "%4d", NULL }; long int_nums[] = { -1, 134, 91340, 341, 0203, 0}; char *str_fmt[] = { "%s", "%5s", "%.5s", "%5.5s", "%5.10s", "%-5.10s", "%10s", "%-10s", "%10.10s", "%-10.10s", "%10.5s", "%-10.5s", "foo: %s :bar", NULL }; char *str = "0123456"; int x, y; int fail = 0; int num = 0; printf ("Testing snprintf format codes against system sprintf...\n"); for (x = 0; fp_fmt[x] != NULL ; x++) for (y = 0; fp_nums[y] != 0 ; y++) { my_snprintf (buf1, sizeof (buf1), fp_fmt[x], fp_nums[y]); sprintf (buf2, fp_fmt[x], fp_nums[y]); if (strcmp (buf1, buf2)) { printf("snprintf doesn't match Format: %s\n\tsnprintf = %s\n\tsprintf = %s\n", fp_fmt[x], buf1, buf2); fail++; } num++; } for (x = 0; int_fmt[x] != NULL ; x++) for (y = 0; int_nums[y] != 0 ; y++) { my_snprintf (buf1, sizeof (buf1), int_fmt[x], int_nums[y]); sprintf (buf2, int_fmt[x], int_nums[y]); if (strcmp (buf1, buf2)) { printf("snprintf doesn't match Format: %s\n\tsnprintf = %s\n\tsprintf = %s\n", int_fmt[x], buf1, buf2); fail++; } num++; } for (x = 0; int_fmt[x] != NULL ; x++) { my_snprintf (buf1, sizeof (buf1), str_fmt[x], str); sprintf (buf2, str_fmt[x], str); if (strcmp (buf1, buf2)) { printf("snprintf doesn't match Format: %s\n\tsnprintf = %s\n\tsprintf = %s\n", str_fmt[x], buf1, buf2); fail++; } num++; } printf ("%d tests failed out of %d.\n", fail, num); exit(0); } #endif /* SNPRINTF_TEST */