Coverage Report

Created: 2023-05-19 06:16

/src/ntp-dev/sntp/libopts/cook.c
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Source (jump to first uncovered line)
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/**
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 * \file cook.c
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 *
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 *  This file contains the routines that deal with processing quoted strings
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 *  into an internal format.
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 *
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 * @addtogroup autoopts
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 * @{
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 */
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/*
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 *  This file is part of AutoOpts, a companion to AutoGen.
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 *  AutoOpts is free software.
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 *  AutoOpts is Copyright (C) 1992-2015 by Bruce Korb - all rights reserved
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 *
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 *  AutoOpts is available under any one of two licenses.  The license
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 *  in use must be one of these two and the choice is under the control
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 *  of the user of the license.
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 *
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 *   The GNU Lesser General Public License, version 3 or later
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 *      See the files "COPYING.lgplv3" and "COPYING.gplv3"
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 *
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 *   The Modified Berkeley Software Distribution License
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 *      See the file "COPYING.mbsd"
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 *
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 *  These files have the following sha256 sums:
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 *
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 *  8584710e9b04216a394078dc156b781d0b47e1729104d666658aecef8ee32e95  COPYING.gplv3
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 *  4379e7444a0e2ce2b12dd6f5a52a27a4d02d39d247901d3285c88cf0d37f477b  COPYING.lgplv3
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 *  13aa749a5b0a454917a944ed8fffc530b784f5ead522b1aacaf4ec8aa55a6239  COPYING.mbsd
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 */
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/* = = = START-STATIC-FORWARD = = = */
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static bool
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contiguous_quote(char ** pps, char * pq, int * lnct_p);
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/* = = = END-STATIC-FORWARD = = = */
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/*=export_func  ao_string_cook_escape_char
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 * private:
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 *
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 * what:  escape-process a string fragment
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 * arg:   + char const * + pzScan  + points to character after the escape +
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 * arg:   + char *       + pRes    + Where to put the result byte +
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 * arg:   + unsigned int + nl_ch   + replacement char if scanned char is \n +
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 *
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 * ret-type: unsigned int
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 * ret-desc: The number of bytes consumed processing the escaped character.
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 *
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 * doc:
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 *
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 *  This function converts "t" into "\t" and all your other favorite
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 *  escapes, including numeric ones:  hex and ocatal, too.
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 *  The returned result tells the caller how far to advance the
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 *  scan pointer (passed in).  The default is to just pass through the
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 *  escaped character and advance the scan by one.
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 *
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 *  Some applications need to keep an escaped newline, others need to
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 *  suppress it.  This is accomplished by supplying a '\n' replacement
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 *  character that is different from \n, if need be.  For example, use
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 *  0x7F and never emit a 0x7F.
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 *
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 * err:  @code{NULL} is returned if the string is mal-formed.
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=*/
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unsigned int
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ao_string_cook_escape_char(char const * pzIn, char * pRes, uint_t nl)
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0
{
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0
    unsigned int res = 1;
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0
    switch (*pRes = *pzIn++) {
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0
    case NUL:         /* NUL - end of input string */
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0
        return 0;
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0
    case '\r':
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0
        if (*pzIn != NL)
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0
            return 1;
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0
        res++;
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        /* FALLTHROUGH */
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0
    case NL:        /* NL  - emit newline        */
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0
        *pRes = (char)nl;
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        return res;
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    case 'a': *pRes = '\a'; break;
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0
    case 'b': *pRes = '\b'; break;
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0
    case 'f': *pRes = '\f'; break;
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0
    case 'n': *pRes = NL;   break;
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0
    case 'r': *pRes = '\r'; break;
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0
    case 't': *pRes = '\t'; break;
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0
    case 'v': *pRes = '\v'; break;
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0
    case 'x':
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0
    case 'X':         /* HEX Escape       */
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0
        if (IS_HEX_DIGIT_CHAR(*pzIn))  {
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0
            char z[4];
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0
            unsigned int ct = 0;
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0
            do  {
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0
                z[ct] = pzIn[ct];
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                if (++ct >= 2)
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                    break;
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0
            } while (IS_HEX_DIGIT_CHAR(pzIn[ct]));
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            z[ct] = NUL;
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0
            *pRes = (char)strtoul(z, NULL, 16);
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0
            return ct + 1;
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0
        }
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0
        break;
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0
    case '0': case '1': case '2': case '3':
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0
    case '4': case '5': case '6': case '7':
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0
    {
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        /*
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         *  IF the character copied was an octal digit,
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         *  THEN set the output character to an octal value.
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         *  The 3 octal digit result might exceed 0xFF, so check it.
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         */
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0
        char z[4];
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0
        unsigned long val;
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0
        unsigned int  ct = 0;
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        z[ct++] = *--pzIn;
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        while (IS_OCT_DIGIT_CHAR(pzIn[ct])) {
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            z[ct] = pzIn[ct];
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            if (++ct >= 3)
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                break;
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        }
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        z[ct] = NUL;
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0
        val = strtoul(z, NULL, 8);
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0
        if (val > 0xFF)
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            val = 0xFF;
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        *pRes = (char)val;
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        return ct;
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0
    }
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    default: /* quoted character is result character */;
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0
    }
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    return res;
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0
}
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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
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 *
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 *  A quoted string has been found.
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 *  Find the end of it and compress any escape sequences.
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 */
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static bool
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contiguous_quote(char ** pps, char * pq, int * lnct_p)
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0
{
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0
    char * ps = *pps + 1;
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    for (;;) {
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0
        while (IS_WHITESPACE_CHAR(*ps))
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0
            if (*(ps++) == NL)
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0
                (*lnct_p)++;
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        /*
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         *  IF the next character is a quote character,
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         *  THEN we will concatenate the strings.
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         */
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0
        switch (*ps) {
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0
        case '"':
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0
        case '\'':
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            *pq  = *(ps++);  /* assign new quote character and return */
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            *pps = ps;
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            return true;
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        case '/':
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            /*
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             *  Allow for a comment embedded in the concatenated string.
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             */
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            switch (ps[1]) {
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0
            default:
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                *pps = NULL;
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                return false;
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            case '/':
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                /*
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                 *  Skip to end of line
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                 */
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0
                ps = strchr(ps, NL);
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0
                if (ps == NULL) {
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0
                    *pps = NULL;
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0
                    return false;
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0
                }
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0
                break;
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0
            case '*':
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0
            {
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0
                char * p = strstr( ps+2, "*/" );
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                /*
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                 *  Skip to terminating star slash
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                 */
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0
                if (p == NULL) {
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0
                    *pps = NULL;
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0
                    return false;
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0
                }
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0
                while (ps < p) {
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0
                    if (*(ps++) == NL)
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0
                        (*lnct_p)++;
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0
                }
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                ps = p + 2;
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0
            }
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0
            }
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0
            continue;
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0
        default:
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            /*
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             *  The next non-whitespace character is not a quote.
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             *  The series of quoted strings has come to an end.
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             */
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0
            *pps = ps;
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0
            return false;
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0
        }
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0
    }
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0
}
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/*=export_func  ao_string_cook
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 * private:
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 *
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 * what:  concatenate and escape-process strings
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 * arg:   + char * + pzScan  + The *MODIFIABLE* input buffer +
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 * arg:   + int *  + lnct_p  + The (possibly NULL) pointer to a line count +
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 *
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 * ret-type: char *
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 * ret-desc: The address of the text following the processed strings.
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 *           The return value is NULL if the strings are ill-formed.
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 *
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 * doc:
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 *
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 *  A series of one or more quoted strings are concatenated together.
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 *  If they are quoted with double quotes (@code{"}), then backslash
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 *  escapes are processed per the C programming language.  If they are
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 *  single quote strings, then the backslashes are honored only when they
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 *  precede another backslash or a single quote character.
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 *
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 * err:  @code{NULL} is returned if the string(s) is/are mal-formed.
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=*/
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char *
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ao_string_cook(char * pzScan, int * lnct_p)
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0
{
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0
    int   l = 0;
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0
    char  q = *pzScan;
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    /*
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     *  It is a quoted string.  Process the escape sequence characters
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     *  (in the set "abfnrtv") and make sure we find a closing quote.
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     */
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0
    char * pzD = pzScan++;
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0
    char * pzS = pzScan;
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0
    if (lnct_p == NULL)
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0
        lnct_p = &l;
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    for (;;) {
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        /*
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         *  IF the next character is the quote character, THEN we may end the
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         *  string.  We end it unless the next non-blank character *after* the
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         *  string happens to also be a quote.  If it is, then we will change
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         *  our quote character to the new quote character and continue
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         *  condensing text.
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         */
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0
        while (*pzS == q) {
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            *pzD = NUL; /* This is probably the end of the line */
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            if (! contiguous_quote(&pzS, &q, lnct_p))
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                return pzS;
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0
        }
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        /*
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         *  We are inside a quoted string.  Copy text.
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         */
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0
        switch (*(pzD++) = *(pzS++)) {
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0
        case NUL:
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            return NULL;
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0
        case NL:
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0
            (*lnct_p)++;
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0
            break;
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0
        case '\\':
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            /*
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             *  IF we are escaping a new line,
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             *  THEN drop both the escape and the newline from
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             *       the result string.
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             */
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0
            if (*pzS == NL) {
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0
                pzS++;
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0
                pzD--;
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0
                (*lnct_p)++;
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0
            }
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            /*
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             *  ELSE IF the quote character is '"' or '`',
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             *  THEN we do the full escape character processing
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             */
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0
            else if (q != '\'') {
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0
                unsigned int ct;
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0
                ct = ao_string_cook_escape_char(pzS, pzD-1, (uint_t)NL);
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0
                if (ct == 0)
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                    return NULL;
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                pzS += ct;
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0
            }     /* if (q != '\'')                  */
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            /*
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             *  OTHERWISE, we only process "\\", "\'" and "\#" sequences.
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             *  The latter only to easily hide preprocessing directives.
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             */
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0
            else switch (*pzS) {
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0
            case '\\':
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0
            case '\'':
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0
            case '#':
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0
                pzD[-1] = *pzS++;
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0
            }
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0
        }     /* switch (*(pzD++) = *(pzS++))    */
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0
    }         /* for (;;)                        */
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0
}
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/** @}
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 *
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 * Local Variables:
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 * mode: C
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 * c-file-style: "stroustrup"
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 * indent-tabs-mode: nil
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 * End:
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 * end of autoopts/cook.c */