/* * $Id: 3da9a5fc88c904673b3b95d0c9667b2bcbccfc80 $ * Time-stamp: "2007-11-16 22:49:11 bkorb" * * This file contains the routines that deal with processing quoted strings * into an internal format. * * This file is part of AutoOpts, a companion to AutoGen. * AutoOpts is free software. * AutoOpts is copyright (c) 1992-2009 by Bruce Korb - all rights reserved * * AutoOpts is available under any one of two licenses. The license * in use must be one of these two and the choice is under the control * of the user of the license. * * The GNU Lesser General Public License, version 3 or later * See the files "COPYING.lgplv3" and "COPYING.gplv3" * * The Modified Berkeley Software Distribution License * See the file "COPYING.mbsd" * * These files have the following md5sums: * * 43b91e8ca915626ed3818ffb1b71248b pkg/libopts/COPYING.gplv3 * 06a1a2e4760c90ea5e1dad8dfaac4d39 pkg/libopts/COPYING.lgplv3 * 66a5cedaf62c4b2637025f049f9b826f pkg/libopts/COPYING.mbsd */ /* = = = START-STATIC-FORWARD = = = */ /* static forward declarations maintained by mk-fwd */ /* = = = END-STATIC-FORWARD = = = */ /*=export_func ao_string_cook_escape_char * private: * * what: escape-process a string fragment * arg: + char const* + pzScan + points to character after the escape + * arg: + char* + pRes + Where to put the result byte + * arg: + unsigned int + nl_ch + replacement char if scanned char is \n + * * ret-type: unsigned int * ret-desc: The number of bytes consumed processing the escaped character. * * doc: * * This function converts "t" into "\t" and all your other favorite * escapes, including numeric ones: hex and ocatal, too. * The returned result tells the caller how far to advance the * scan pointer (passed in). The default is to just pass through the * escaped character and advance the scan by one. * * Some applications need to keep an escaped newline, others need to * suppress it. This is accomplished by supplying a '\n' replacement * character that is different from \n, if need be. For example, use * 0x7F and never emit a 0x7F. * * err: @code{NULL} is returned if the string is mal-formed. =*/ unsigned int ao_string_cook_escape_char( char const* pzIn, char* pRes, u_int nl ) { unsigned int res = 1; switch (*pRes = *pzIn++) { case NUL: /* NUL - end of input string */ return 0; case '\r': if (*pzIn != '\n') return 1; res++; /* FALLTHROUGH */ case '\n': /* NL - emit newline */ *pRes = (char)nl; return res; case 'a': *pRes = '\a'; break; case 'b': *pRes = '\b'; break; case 'f': *pRes = '\f'; break; case 'n': *pRes = '\n'; break; case 'r': *pRes = '\r'; break; case 't': *pRes = '\t'; break; case 'v': *pRes = '\v'; break; case 'x': case 'X': /* HEX Escape */ if (IS_HEX_DIGIT_CHAR(*pzIn)) { char z[4], *pz = z; do *(pz++) = *(pzIn++); while (IS_HEX_DIGIT_CHAR(*pzIn) && (pz < z + 2)); *pz = NUL; *pRes = (unsigned char)strtoul(z, NULL, 16); res += pz - z; } break; case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': { /* * IF the character copied was an octal digit, * THEN set the output character to an octal value */ char z[4], *pz = z + 1; unsigned long val; z[0] = *pRes; while (IS_OCT_DIGIT_CHAR(*pzIn) && (pz < z + 3)) *(pz++) = *(pzIn++); *pz = NUL; val = strtoul(z, NULL, 8); if (val > 0xFF) val = 0xFF; *pRes = (unsigned char)val; res = pz - z; break; } default: ; } return res; } /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * A quoted string has been found. * Find the end of it and compress any escape sequences. */ /*=export_func ao_string_cook * private: * * what: concatenate and escape-process strings * arg: + char* + pzScan + The *MODIFIABLE* input buffer + * arg: + int* + pLineCt + The (possibly NULL) pointer to a line count + * * ret-type: char* * ret-desc: The address of the text following the processed strings. * The return value is NULL if the strings are ill-formed. * * doc: * * A series of one or more quoted strings are concatenated together. * If they are quoted with double quotes (@code{"}), then backslash * escapes are processed per the C programming language. If they are * single quote strings, then the backslashes are honored only when they * precede another backslash or a single quote character. * * err: @code{NULL} is returned if the string(s) is/are mal-formed. =*/ char* ao_string_cook( char* pzScan, int* pLineCt ) { int l = 0; char q = *pzScan; /* * It is a quoted string. Process the escape sequence characters * (in the set "abfnrtv") and make sure we find a closing quote. */ char* pzD = pzScan++; char* pzS = pzScan; if (pLineCt == NULL) pLineCt = &l; for (;;) { /* * IF the next character is the quote character, THEN we may end the * string. We end it unless the next non-blank character *after* the * string happens to also be a quote. If it is, then we will change * our quote character to the new quote character and continue * condensing text. */ while (*pzS == q) { *pzD = NUL; /* This is probably the end of the line */ pzS++; scan_for_quote: while (IS_WHITESPACE_CHAR(*pzS)) if (*(pzS++) == '\n') (*pLineCt)++; /* * IF the next character is a quote character, * THEN we will concatenate the strings. */ switch (*pzS) { case '"': case '\'': break; case '/': /* * Allow for a comment embedded in the concatenated string. */ switch (pzS[1]) { default: return NULL; case '/': /* * Skip to end of line */ pzS = strchr( pzS, '\n' ); if (pzS == NULL) return NULL; (*pLineCt)++; break; case '*': { char* p = strstr( pzS+2, "*/" ); /* * Skip to terminating star slash */ if (p == NULL) return NULL; while (pzS < p) { if (*(pzS++) == '\n') (*pLineCt)++; } pzS = p + 2; } } goto scan_for_quote; default: /* * The next non-whitespace character is not a quote. * The series of quoted strings has come to an end. */ return pzS; } q = *(pzS++); /* assign new quote character and advance scan */ } /* * We are inside a quoted string. Copy text. */ switch (*(pzD++) = *(pzS++)) { case NUL: return NULL; case '\n': (*pLineCt)++; break; case '\\': /* * IF we are escaping a new line, * THEN drop both the escape and the newline from * the result string. */ if (*pzS == '\n') { pzS++; pzD--; (*pLineCt)++; } /* * ELSE IF the quote character is '"' or '`', * THEN we do the full escape character processing */ else if (q != '\'') { int ct = ao_string_cook_escape_char( pzS, pzD-1, (u_int)'\n' ); if (ct == 0) return NULL; pzS += ct; } /* if (q != '\'') */ /* * OTHERWISE, we only process "\\", "\'" and "\#" sequences. * The latter only to easily hide preprocessing directives. */ else switch (*pzS) { case '\\': case '\'': case '#': pzD[-1] = *pzS++; } } /* switch (*(pzD++) = *(pzS++)) */ } /* for (;;) */ } /* * Local Variables: * mode: C * c-file-style: "stroustrup" * indent-tabs-mode: nil * End: * end of autoopts/cook.c */