/* $OpenBSD: safe_sprintf.c,v 1.5 1998/09/13 19:16:30 millert Exp $ */ /**************************************************************************** * Copyright (c) 1998 Free Software Foundation, Inc. * * * * Permission is hereby granted, free of charge, to any person obtaining a * * copy of this software and associated documentation files (the * * "Software"), to deal in the Software without restriction, including * * without limitation the rights to use, copy, modify, merge, publish, * * distribute, distribute with modifications, sublicense, and/or sell * * copies of the Software, and to permit persons to whom the Software is * * furnished to do so, subject to the following conditions: * * * * The above copyright notice and this permission notice shall be included * * in all copies or substantial portions of the Software. * * * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR * * THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * * * Except as contained in this notice, the name(s) of the above copyright * * holders shall not be used in advertising or otherwise to promote the * * sale, use or other dealings in this Software without prior written * * authorization. * ****************************************************************************/ /**************************************************************************** * Author: Thomas E. Dickey 1997 * ****************************************************************************/ #include #include MODULE_ID("$From: safe_sprintf.c,v 1.9 1998/08/15 23:58:49 tom Exp $") #if USE_SAFE_SPRINTF typedef enum { Flags, Width, Prec, Type, Format } PRINTF; #define VA_INTGR(type) ival = va_arg(ap, type) #define VA_FLOAT(type) fval = va_arg(ap, type) #define VA_POINT(type) pval = (void *)va_arg(ap, type) /* * Scan a variable-argument list for printf to determine the number of * characters that would be emitted. */ static int _nc_printf_length(const char *fmt, va_list ap) { size_t length = BUFSIZ; char *buffer; char *format; int len = 0; if (fmt == 0 || *fmt == '\0') return -1; if ((format = malloc(strlen(fmt)+1)) == 0) return -1; if ((buffer = malloc(length)) == 0) { free(format); return -1; } while (*fmt != '\0') { if (*fmt == '%') { static char dummy[] = ""; PRINTF state = Flags; char *pval = dummy; /* avoid const-cast */ double fval = 0.0; int done = FALSE; int ival = 0; int prec = -1; int type = 0; int used = 0; int width = -1; size_t f = 0; format[f++] = *fmt; while (*++fmt != '\0' && len >= 0 && !done) { format[f++] = *fmt; if (isdigit(*fmt)) { int num = *fmt - '0'; if (state == Flags && num != 0) state = Width; if (state == Width) { if (width < 0) width = 0; width = (width * 10) + num; } else if (state == Prec) { if (prec < 0) prec = 0; prec = (prec * 10) + num; } } else if (*fmt == '*') { VA_INTGR(int); if (state == Flags) state = Width; if (state == Width) { width = ival; } else if (state == Prec) { prec = ival; } sprintf(&format[--f], "%d", ival); f = strlen(format); } else if (isalpha(*fmt)) { done = TRUE; switch (*fmt) { case 'Z': /* FALLTHRU */ case 'h': /* FALLTHRU */ case 'l': /* FALLTHRU */ case 'L': /* FALLTHRU */ done = FALSE; type = *fmt; break; case 'i': /* FALLTHRU */ case 'd': /* FALLTHRU */ case 'u': /* FALLTHRU */ case 'x': /* FALLTHRU */ case 'X': /* FALLTHRU */ if (type == 'l') VA_INTGR(long); else if (type == 'Z') VA_INTGR(size_t); else VA_INTGR(int); used = 'i'; break; case 'f': /* FALLTHRU */ case 'e': /* FALLTHRU */ case 'E': /* FALLTHRU */ case 'g': /* FALLTHRU */ case 'G': /* FALLTHRU */ if (type == 'L') VA_FLOAT(long double); else VA_FLOAT(double); used = 'f'; break; case 'c': VA_INTGR(int); used = 'i'; break; case 's': VA_POINT(char *); if (prec < 0) prec = strlen(pval); if (prec > (int)length) { length = length + prec; buffer = (char *)_nc_doalloc(buffer, length); if (buffer == 0) { free(format); return -1; } } used = 'p'; break; case 'p': VA_POINT(void *); used = 'p'; break; case 'n': VA_POINT(int *); used = 0; break; default: break; } } else if (*fmt == '.') { state = Prec; } else if (*fmt == '%') { done = TRUE; used = 'p'; } } format[f] = '\0'; switch (used) { case 'i': sprintf(buffer, format, ival); break; case 'f': sprintf(buffer, format, fval); break; default: sprintf(buffer, format, pval); break; } len += (int)strlen(buffer); } else { fmt++; len++; } } free(buffer); free(format); return len; } #endif /* * Wrapper for vsprintf that allocates a buffer big enough to hold the result. */ char * _nc_printf_string(const char *fmt, va_list ap) { #if USE_SAFE_SPRINTF char *buf = 0; int len = _nc_printf_length(fmt, ap); if (len > 0) { if ((buf = malloc(len+1)) == 0) return(0); vsprintf(buf, fmt, ap); } #else static int rows, cols; static char *buf; static size_t len; if (screen_lines > rows || screen_columns > cols) { if (screen_lines > rows) rows = screen_lines; if (screen_columns > cols) cols = screen_columns; len = (rows * (cols + 1)) + 1; buf = (char *)_nc_doalloc(buf, len); if (buf == 0) { return(0); } } if (buf != 0) { # if HAVE_VSNPRINTF vsnprintf(buf, len, fmt, ap); /* GNU extension */ # else vsprintf(buf, fmt, ap); /* ANSI */ # endif } #endif return buf; }