/**************************************************************************** * libs/libc/stdio/lib_libsscanf.c * * Copyright (C) 2007, 2008, 2011-2014, 2016, 2019 Gregory Nutt. All rights * reserved. * Author: Gregory Nutt * Johannes Schock * * 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 NuttX 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 COPYRIGHT HOLDERS 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 * COPYRIGHT OWNER 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. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include "libc.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #define MAXLN 128 #define HH_MOD -2 #define H_MOD -1 #define NO_MOD 0 #define L_MOD 1 #define LL_MOD 2 #ifndef MIN # define MIN(a,b) (((a) < (b)) ? (a) : (b)) #endif #ifndef MAX # define MAX(a,b) (((a) > (b)) ? (a) : (b)) #endif /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: findscanset * * Description: * Fill in the given table from the scanset at the given format. * Return a pointer to the character the closing ']'. * The table has a 1 wherever characters should be considered part of the * scanset. * * Function findscanset based on source function __sccl of FreeBSD * (https://github.com/lattera/freebsd/blob/master/sys/kern/subr_scanf.c) * ****************************************************************************/ #ifdef CONFIG_LIBC_SCANSET static FAR const char *findscanset(FAR const char *fmt, FAR unsigned char set[32]) { int c; int n; int v; int i; fmt++; /* Skip '[' */ /* First `clear' the whole table */ c = *fmt++; /* First char hat => negated scanset */ if (c == '^') { v = 1; /* Default => accept */ c = *fmt++; /* Get new first char */ } else { v = 0; /* Default => reject */ } memset(set, 0, 32); if (c == 0) { goto doexit; } /* Now set the entries corresponding to the actual scanset to the opposite * of the above. The first character may be ']' (or '-') without being * special; the last character may be '-'. */ for (; ; ) { set[c / 8] |= (1 << (c % 8)); /* Take character c */ doswitch:n = *fmt++; /* Examine the next */ switch (n) { case 0: /* Format ended too soon */ case ']': /* End of scanset */ goto doexit; case '-': /* A scanset of the form [01+-] is defined as "the digit 0, the * digit 1, the character +, the character -", but the effect of a * scanset such as [a-zA-Z0-9] is implementation defined. The V7 * Unix scanf treats "a-z" as "the letters a through z", but treats * "a-a" as "the letter a, the character -, and the letter a". For * compatibility, the `-' is not considerd to define a range if the * character following it is either a close bracket (required by * ANSI) or is not numerically greater than the character* we just * stored in the table (c). */ n = *fmt; if (n == ']' || n < c) { c = '-'; break; /* Resume the for(;;) */ } fmt++; do { /* Fill in the range */ c++; set[c / 8] |= (1 << (c % 8)); /* Take character c */ } while (c < n); /* Alas, the V7 Unix scanf also treats formats such as [a-c-e] as * "the letters a through e". This too is permitted by the * standard. */ goto doswitch; default: /* Just another character */ c = n; break; } } doexit: if (v) /* Default => accept */ { for (i = 0; i < 32; i++) /* Invert all */ { set[i] ^= 0xff; } } return (fmt - 1); } #endif /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: lib_vscanf * * Description: * Stream-oriented implementation that underlies scanf family: scanf, * fscanf, vfscanf, sscanf, and vsscanf * ****************************************************************************/ int lib_vscanf(FAR struct lib_instream_s *obj, FAR int *lastc, FAR const IPTR char *fmt, va_list ap) { int c; FAR char *tv; FAR const char *tc; int modifier; bool noassign; bool conv; int assigncount; int count; int ngetstart; int width; int fwidth; int base = 10; char tmp[MAXLN]; #ifdef CONFIG_LIBC_LONG_LONG FAR unsigned long long *plonglong = NULL; #endif FAR unsigned long *plong = NULL; FAR unsigned int *pint = NULL; FAR unsigned short *pshort = NULL; FAR unsigned char *pchar = NULL; #ifdef CONFIG_LIBC_SCANSET unsigned char set[32]; /* Bit field (256 / 8) */ #endif /* keep this for future reference linfo("buf=\"%s\" fmt=\"%s\"\n", buf, fmt); */ /* Parse the format, extracting values from the input buffer as needed */ assigncount = 0; count = 0; width = 0; conv = false; noassign = false; modifier = NO_MOD; ngetstart = obj->nget; /* for %n calculations */ /* Make sure lastc is not NULL. */ if (lastc == NULL) { lastc = &c; } /* Loop until all characters in the fmt string have been processed. We may * have to continue loop after reaching the end the input data in order to * handle trailing %n format specifiers. */ /* Get first character, we keep always the next character in c */ c = obj->get(obj); while (*fmt) { /* Skip over white spaces */ if (isspace(*fmt)) { while (isspace(c)) { c = obj->get(obj); } } while (isspace(*fmt)) { fmt++; } /* Check for a conversion specifier */ if (*fmt == '%') { linfo("Specifier found\n"); /* Check for qualifiers on the conversion specifier */ fmt++; for (; *fmt; fmt++) { linfo("Processing %c\n", *fmt); #ifdef CONFIG_LIBC_SCANSET if (strchr("dibouxXcseEfFgGaAn[%", *fmt)) #else if (strchr("dibouxXcseEfFgGaAn%", *fmt)) #endif { if (*fmt != '%') { conv = true; } break; } if (*fmt == '*') { noassign = true; } else if (*fmt == 'l' || *fmt == 'L') { modifier = L_MOD; if (*(fmt + 1) == 'l' || *(fmt + 1) == 'L') { modifier = LL_MOD; fmt++; } } else if (*fmt == 'h' || *fmt == 'H') { modifier = H_MOD; if (*(fmt + 1) == 'h' || *(fmt + 1) == 'H') { modifier = HH_MOD; fmt++; } } else if (*fmt >= '1' && *fmt <= '9') { for (tc = fmt; isdigit(*fmt); fmt++) ; strncpy(tmp, tc, fmt - tc); tmp[fmt - tc] = '\0'; width = atoi(tmp); fmt--; } } /* Process %s: String conversion */ if (*fmt == 's') { linfo("Performing string conversion\n"); /* Get a pointer to the char * value. We need to do this even * of we have reached the end of the input data in order to * update the 'ap' variable. */ tv = NULL; /* To avoid warnings about begin uninitialized */ if (!noassign) { tv = va_arg(ap, FAR char *); tv[0] = '\0'; } /* Skip over white space */ while (isspace(c)) { c = obj->get(obj); } /* But we only perform the data conversion is we still have * bytes remaining in the input data stream. */ if (c > 0) { /* Use the actual field's width if 1) no fieldwidth * specified or 2) the actual field's width is smaller * than fieldwidth specified. */ fwidth = 0; while ((!width || (fwidth < width)) && (c > 0) && !isspace(c)) { if (!noassign) { tv[fwidth] = c; } fwidth++; c = obj->get(obj); } if (!noassign) { tv[fwidth] = '\0'; assigncount++; } count++; } } #ifdef CONFIG_LIBC_SCANSET /* Process %[: Scanset conversion */ if (*fmt == '[') { linfo("Performing scanset conversion\n"); fmt = findscanset(fmt, set); /* find scanset */ /* Get a pointer to the char * value. We need to do this even * if we have reached the end of the input data in order to * update the 'ap' variable. */ tv = NULL; /* To avoid warnings about begin uninitialized */ if (!noassign) { tv = va_arg(ap, FAR char *); tv[0] = '\0'; } /* But we only perform the data conversion is we still have * bytes remaining in the input data stream. */ if (c > 0) { /* Use the actual field's width if 1) no fieldwidth * specified or 2) the actual field's width is smaller * than the fieldwidth specified. */ fwidth = 0; while ((!width || (fwidth < width)) && (c > 0) && ((set[c / 8] & (1 << (c % 8))) != 0)) { if (!noassign) { tv[fwidth] = c; } fwidth++; c = obj->get(obj); } if (!fwidth) { *lastc = c; return assigncount; } if (!noassign) { tv[fwidth] = '\0'; assigncount++; } count++; } } #endif /* Process %c: Character conversion */ else if (*fmt == 'c') { linfo("Performing character conversion\n"); /* Get a pointer to the char * value. We need to do this even * if we have reached the end of the input data in order to * update the 'ap' variable. */ tv = NULL; /* To avoid warnings about being uninitialized */ if (!noassign) { tv = va_arg(ap, FAR char *); tv[0] = '\0'; } /* But we only perform the data conversion is we still have * bytes remaining in the input data stream. */ if (c > 0) { /* Was a field width specified? */ if (!width) { /* No, then width is this one single character */ width = 1; } /* Copy the character(s) (if we are making an assignment) */ fwidth = 0; while ((fwidth < width) && c > 0) { if (!noassign) { tv[fwidth] = c; } fwidth++; c = obj->get(obj); } if (fwidth != width) { *lastc = c; return assigncount; } if (!noassign) { assigncount++; } count++; } } /* Process %d, %o, %b, %x, %u: Various integer conversions */ else if (strchr("dobxXui", *fmt)) { bool sign; linfo("Performing integer conversion\n"); /* Get a pointer to the integer value. We need to do this even * if we have reached the end of the input data in order to * update the 'ap' variable. */ if (!noassign) { /* We have to check whether we need to return a long or an * int. */ switch (modifier) { case HH_MOD: pchar = va_arg(ap, FAR unsigned char *); *pchar = 0; break; case H_MOD: pshort = va_arg(ap, FAR unsigned short *); *pshort = 0; break; case NO_MOD: pint = va_arg(ap, FAR unsigned int *); *pint = 0; break; default: case L_MOD: plong = va_arg(ap, FAR unsigned long *); *plong = 0; break; #ifdef CONFIG_LIBC_LONG_LONG case LL_MOD: plonglong = va_arg(ap, FAR unsigned long long *); *plonglong = 0; break; #endif } } /* Skip over any white space before the integer string */ while (isspace(c)) { c = obj->get(obj); } /* But we only perform the data conversion if we still have * bytes remaining in the input data stream. */ if (c > 0) { FAR char *endptr; int prefix; bool stopconv; int errsave; unsigned long tmplong = 0; #ifdef CONFIG_LIBC_LONG_LONG unsigned long long tmplonglong = 0; #endif /* Copy the real string into a temporary working buffer. */ if (!width || width > sizeof(tmp) - 1) { width = sizeof(tmp) - 1; } /* The base of the integer conversion depends on the * specific conversion specification. */ fwidth = 0; prefix = 0; stopconv = false; sign = false; switch (*fmt) { default: case 'd': sign = true; /* FALLTHROUGH */ case 'u': while (fwidth < width && !stopconv) { if (c == '-' || c == '+') { if (fwidth != 0) { stopconv = true; } } else if (!(c >= '0' && c <= '9')) { stopconv = true; } if (!stopconv) { tmp[fwidth++] = c; c = obj->get(obj); } } base = 10; break; case 'x': case 'X': while (fwidth < width && !stopconv) { if (c == '-' || c == '+') { if (fwidth != 0) { stopconv = true; } } else if (c == '0') { if (prefix == 0) { prefix = 1; } } else if (c == 'x' || c == 'X') { if (prefix == 1) { prefix = 2; } else { stopconv = true; } } else if (!((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F'))) { stopconv = true; } else { prefix = 2; } if (!stopconv) { tmp[fwidth++] = c; c = obj->get(obj); } } base = 16; break; case 'o': while (fwidth < width && !stopconv) { if (c == '-' || c == '+') { if (fwidth != 0) { stopconv = true; } } else if (!(c >= '0' && c <= '7')) { stopconv = true; } if (!stopconv) { tmp[fwidth++] = c; c = obj->get(obj); } } base = 8; break; case 'b': /* not official? */ while (fwidth < width && !stopconv) { if (c == '-' || c == '+') { if (fwidth != 0) { stopconv = true; } } else if (!(c >= '0' && c <= '1')) { stopconv = true; } if (!stopconv) { tmp[fwidth++] = c; c = obj->get(obj); } } base = 2; break; case 'i': sign = true; base = 10; while (fwidth < width && !stopconv) { if (c == '-' || c == '+') { if (fwidth != 0) { stopconv = true; } } else if (c == '0') { if (prefix == 0) { prefix = 1; base = 8; } } else if (c == 'x' || c == 'X') { if (prefix == 1) { prefix = 2; base = 16; } else { stopconv = true; } } else if (!((c >= '0' && c <= '7' && base >= 8) || (c >= '8' && c <= '9' && base >= 10) || (c >= 'a' && c <= 'f' && base == 16) || (c >= 'A' && c <= 'F' && base == 16))) { stopconv = true; } else { prefix = 2; } if (!stopconv) { tmp[fwidth++] = c; c = obj->get(obj); } } break; } tmp[fwidth] = 0; linfo("tmp[]=\"%s\"\n", tmp); /* Perform the integer conversion */ /* Preserve the errno value */ errsave = get_errno(); set_errno(0); switch (modifier) { #ifndef CONFIG_LIBC_LONG_LONG case LL_MOD: #endif case HH_MOD: case H_MOD: case NO_MOD: default: if (sign) { tmplong = strtol(tmp, &endptr, base); } else { tmplong = strtoul(tmp, &endptr, base); } break; #ifdef CONFIG_LIBC_LONG_LONG case LL_MOD: if (sign) { tmplonglong = strtoll(tmp, &endptr, base); } else { tmplonglong = strtoull(tmp, &endptr, base); } break; #endif } /* Check if the number was successfully converted */ if (tmp == endptr || get_errno() == ERANGE) { *lastc = c; return assigncount; } set_errno(errsave); if (!noassign) { /* We have to check whether we need to return a long or * an int. */ switch (modifier) { case HH_MOD: linfo("Return %ld to 0x%p\n", tmplong, pchar); *pchar = (unsigned char)tmplong; break; case H_MOD: linfo("Return %ld to 0x%p\n", tmplong, pshort); *pshort = (unsigned short)tmplong; break; case NO_MOD: linfo("Return %ld to 0x%p\n", tmplong, pint); *pint = (unsigned int)tmplong; break; #ifndef CONFIG_LIBC_LONG_LONG case L_MOD: #endif default: linfo("Return %ld to 0x%p\n", tmplong, plong); *plong = tmplong; break; #ifdef CONFIG_LIBC_LONG_LONG case LL_MOD: linfo("Return %lld to 0x%p\n", tmplonglong, plonglong); *plonglong = tmplonglong; break; #endif } assigncount++; } count++; } } /* Process %a, %A, %f, %F, %e, %E, %g, and %G: Floating point * conversions. */ else if (strchr("aAfFeEgG", *fmt) != NULL) { #ifdef CONFIG_HAVE_DOUBLE FAR double *pd = NULL; #endif FAR float *pf = NULL; linfo("Performing floating point conversion\n"); /* Get a pointer to the double value. We need to do this even * if we have reached the end of the input data in order to * upate the 'ap' variable. */ if (!noassign) { /* We have to check whether we need to return a float or a * double. */ #ifdef CONFIG_HAVE_DOUBLE if (modifier >= L_MOD) { pd = va_arg(ap, FAR double *); *pd = 0.0; } else #endif { pf = va_arg(ap, FAR float *); *pf = 0.0; } } #ifdef CONFIG_LIBC_FLOATINGPOINT /* Skip over any white space before the real string */ while (isspace(c)) { c = obj->get(obj); } /* But we only perform the data conversion is we still have * bytes remaining in the input data stream. */ if (c > 0) { FAR char *endptr; bool expnt; bool dot; bool sign; bool stopconv; int errsave; # ifdef CONFIG_HAVE_DOUBLE double dvalue; # endif float fvalue; /* Was a fieldwidth specified? */ if (!width || width > sizeof(tmp) - 1) { width = sizeof(tmp) - 1; } /* Copy the real string into a temporary working buffer. */ fwidth = 0; expnt = false; sign = false; dot = false; stopconv = false; while (fwidth < width && !stopconv) { if (c == '-' || c == '+') { if (!sign) { sign = true; } else { stopconv = true; } } else if (c == '.') { if (!dot) { dot = true; sign = true; } else { stopconv = true; } } else if (c == 'e' || c == 'E') { if (!expnt) { expnt = true; sign = false; } else { stopconv = true; } } else if (!(c >= '0' && c <= '9')) { stopconv = true; } else { sign = true; } if (!stopconv) { tmp[fwidth++] = c; c = obj->get(obj); } } tmp[fwidth] = 0; linfo("tmp[]=\"%s\"\n", tmp); /* Perform the floating point conversion */ /* Preserve the errno value */ errsave = get_errno(); set_errno(0); # ifdef CONFIG_HAVE_DOUBLE if (modifier >= L_MOD) { /* Get the converted double value */ dvalue = strtod(tmp, &endptr); } else # endif { fvalue = strtof(tmp, &endptr); } /* Check if the number was successfully converted */ if (tmp == endptr || get_errno() == ERANGE) { *lastc = c; return assigncount; } set_errno(errsave); if (!noassign) { /* We have to check whether we need to return a float or * a double. */ # ifdef CONFIG_HAVE_DOUBLE if (modifier >= L_MOD) { /* Return the double value */ linfo("Return %f to %p\n", dvalue, pd); *pd = dvalue; } else # endif { /* Return the float value */ linfo("Return %f to %p\n", (double)fvalue, pf); *pf = fvalue; } assigncount++; } count++; } #endif } /* Process %n: Character count */ else if (*fmt == 'n') { linfo("Performing character count\n"); if (!noassign) { size_t nchars = (size_t) (obj->nget - ngetstart); if (c != EOF) { /* One more character already read */ nchars--; } /* Note %n does not count as a conversion */ switch (modifier) { case HH_MOD: pchar = va_arg(ap, FAR unsigned char *); *pchar = (unsigned char)nchars; break; case H_MOD: pshort = va_arg(ap, FAR unsigned short *); *pshort = (unsigned short)nchars; break; case NO_MOD: pint = va_arg(ap, FAR unsigned int *); *pint = (unsigned int)nchars; break; default: case L_MOD: plong = va_arg(ap, FAR unsigned long *); *plong = (unsigned long)nchars; break; #ifdef CONFIG_LIBC_LONG_LONG case LL_MOD: plonglong = va_arg(ap, FAR unsigned long long *); *plonglong = (unsigned long long)nchars; break; #endif } } count++; } else if (*fmt == '%') { if (c != '%') { break; } else { c = obj->get(obj); } } width = 0; noassign = false; modifier = NO_MOD; fmt++; } /* It is not a conversion specifier */ else if (c > 0) { #if 0 /* Skip over any leading spaces in the input buffer */ while (isspace(c)) { c = obj->get(obj); } #endif /* Skip over matching characters in the buffer and format */ if (*fmt != c) { break; } else { fmt++; c = obj->get(obj); } } else { /* NULL terminator encountered */ break; } } /* sscanf is required to return EOF if the input ends before the first * matching failure or conversion. */ *lastc = c; return (count || !conv) ? assigncount : EOF; }