htstring.c

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/*
 * Returns a quoted or escaped form of the given parameter, suitable for use in
 * a command string.
 */
#if USE_QUOTED_PARAMETER
#define S_QUOTE '\''
#define D_QUOTE '"'
PUBLIC char *HTQuoteParameter ARGS1(
    CONST char *,	parameter)
{
    size_t i;
    size_t last = strlen(parameter);
    size_t n = 0;
    size_t quoted = 0;
    char * result;

    for (i=0; i < last; ++i)
	if (strchr("\\&#$^*?(){}<>\"';`|", parameter[i]) != 0
	 || isspace(UCH(parameter[i])))
	    ++quoted;

    result = (char *)malloc(last + 5*quoted + 3);
    if (result == NULL)
	outofmem(__FILE__, "HTQuoteParameter");

    n = 0;
    if (quoted)
	result[n++] = S_QUOTE;
    for (i = 0; i < last; i++) {
	if (parameter[i] == S_QUOTE) {
	    result[n++] = S_QUOTE;
	    result[n++] = D_QUOTE;
	    result[n++] = parameter[i];
	    result[n++] = D_QUOTE;
	    result[n++] = S_QUOTE;
	} else {
	    /* Note:  No special handling of other characters, including
	       backslash, since we are constructing a single-quoted string!
	       Backslash has no special escape meaning within those for sh
	       and compatible shells, so trying to escape a backslash by
	       doubling it is unnecessary and would be interpreted by the
	       shell as an additional data character. - kw 2000-05-02
	       */
	    result[n++] = parameter[i];
	}
    }
    if (quoted)
	result[n++] = S_QUOTE;
    result[n] = '\0';
    return result;
}
#endif

#define HTIsParam(string) ((string[0] == '%' && string[1] == 's'))

/*
 * Returns the number of "%s" tokens in a system command-template.
 */
PUBLIC int HTCountCommandArgs ARGS1(
    CONST char *,	command)
{
    int number = 0;
    while (command[0] != 0) {
	if (HTIsParam(command))
	    number++;
	command++;
    }
    return number;
}

/*
 * Returns a pointer into the given string after the given parameter number
 */
PRIVATE CONST char *HTAfterCommandArg ARGS2(
    CONST char *,	command,
    int,		number)
{
    while (number > 0) {
	if (command[0] != 0) {
	    if (HTIsParam(command)) {
		number--;
		command++;
	    }
	    command++;
	} else {
	    break;
	}
    }
    return command;
}

/*
 * Like HTAddParam, but the parameter may be an environment variable, which we
 * will expand and append.  Do this only for things like the command-verb,
 * where we obtain the parameter from the user's configuration.  Any quoting
 * required for the environment variable has to be done within its value, e.g.,
 *
 *	setenv EDITOR 'xvile -name "No such class"'
 *
 * This is useful only when we quote parameters, of course.
 */
#if USE_QUOTED_PARAMETER
PUBLIC void HTAddXpand ARGS4(
    char **,		result,
    CONST char *,	command,
    int,		number,
    CONST char *,	parameter)
{
    if (number > 0) {
	CONST char *last = HTAfterCommandArg(command, number - 1);
	CONST char *next = last;

	if (number <= 1) {
	    FREE(*result);
	}

	while (next[0] != 0) {
	    if (HTIsParam(next)) {
		if (next != last) {
		    size_t len = (next - last)
				+ ((*result != 0) ? strlen(*result) : 0);
		    HTSACat(result, last);
		    (*result)[len] = 0;
		}
		HTSACat(result, parameter);
		CTRACE((tfp, "PARAM-EXP:%s\n", *result));
		return;
	    }
	    next++;
	}
    }
}
#endif /* USE_QUOTED_PARAMETER */

/*
 * Append string to a system command that we are constructing, without quoting. 
 * We're given the index of the newest parameter we're processing.  Zero
 * indicates none, so a value of '1' indicates that we copy from the beginning
 * of the command string up to the first parameter, substitute the quoted
 * parameter and return the result.
 *
 * Parameters are substituted at "%s" tokens, like printf.  Other printf-style
 * tokens are not substituted; they are passed through without change.
 */
PUBLIC void HTAddToCmd ARGS4(
    char **,		result,
    CONST char *,	command,
    int,		number,
    CONST char *,	string)
{
    if (number > 0) {
	CONST char *last = HTAfterCommandArg(command, number - 1);
	CONST char *next = last;

	if (number <= 1) {
	    FREE(*result);
	}
	if (string == 0)
	    string = "";
	while (next[0] != 0) {
	    if (HTIsParam(next)) {
		if (next != last) {
		    size_t len = (next - last)
				+ ((*result != 0) ? strlen(*result) : 0);
		    HTSACat(result, last);
		    (*result)[len] = 0;
		}
		HTSACat(result, string);
		CTRACE((tfp, "PARAM-ADD:%s\n", *result));
		return;
	    }
	    next++;
	}
    }
}

/*
 * Append string-parameter to a system command that we are constructing.  The
 * string is a complete parameter (which is a necessary assumption so we can
 * quote it properly).
 */
PUBLIC void HTAddParam ARGS4(
    char **,		result,
    CONST char *,	command,
    int,		number,
    CONST char *,	parameter)
{
    if (number > 0) {
#if USE_QUOTED_PARAMETER
	char *quoted = HTQuoteParameter(parameter);
	HTAddToCmd(result, command, number, quoted);
	FREE(quoted);
#else
	HTAddToCmd(result, command, number, parameter);
#endif
    }
}

/*
 * Append the remaining command-string to a system command (compare with
 * HTAddParam).  Any remaining "%s" tokens are copied as empty strings.
 */
PUBLIC void HTEndParam ARGS3(
    char **,		result,
    CONST char *,	command,
    int,		number)
{
    CONST char *last;
    int count;

    count = HTCountCommandArgs (command);
    if (count < number)
	number = count;
    last = HTAfterCommandArg(command, number);
    if (last[0] != 0) {
	HTSACat(result, last);
    }
    CTRACE((tfp, "PARAM-END:%s\n", *result));
}


/*	Binary-strings (may have embedded nulls).
 *	Some modules (HTGopher) assume there is a null on the end, anyway.
 */

/*	Allocate a new bstring, and return it.
*/
PUBLIC void HTSABCopy ARGS3(
	bstring**,	dest,
	CONST char *,	src,
	int,		len)
{
    bstring *t;
    unsigned need = len + 1;

    CTRACE2(TRACE_BSTRING, (tfp, "HTSABCopy(%p, %p, %d)\n", dest, src, len));
    HTSABFree(dest);
    if (src) {
	if (TRACE_BSTRING) {
	    CTRACE((tfp, "===    %4d:", len));
	    trace_bstring2(src, len);
	    CTRACE((tfp, "\n"));
	}
	if ((t = (bstring*) malloc(sizeof(bstring))) == NULL)
	    outofmem(__FILE__, "HTSABCopy");
	if ((t->str = (char *) malloc (need)) == NULL)
	    outofmem(__FILE__, "HTSABCopy");
	memcpy (t->str, src, len);
	t->len = len;
	t->str[t->len] = '\0';
	*dest = t;
    }
    if (TRACE_BSTRING) {
	CTRACE((tfp, "=>     %4d:", BStrLen(*dest)));
	trace_bstring(*dest);
	CTRACE((tfp, "\n"));
    }
}

/*
 * Initialize with a null-terminated string (discards the null).
 */
PUBLIC void HTSABCopy0 ARGS2(
	bstring**,	dest,
	CONST char *,	src)
{
    HTSABCopy(dest, src, strlen(src));
}

/*
 * Append a block of memory to a bstring.
 */
PUBLIC void HTSABCat ARGS3(
	bstring **,	dest,
	CONST char *,	src,
	int,		len)
{
    bstring *t = *dest;

    CTRACE2(TRACE_BSTRING, (tfp, "HTSABCat(%p, %p, %d)\n", dest, src, len));
    if (src) {
	unsigned need = len + 1;

	if (TRACE_BSTRING) {
	    CTRACE((tfp, "===    %4d:", len));
	    trace_bstring2(src, len);
	    CTRACE((tfp, "\n"));
	}
	if (t) {
	    unsigned length = t->len + need;
	    if ((t->str = (char *)realloc(t->str, length)) == NULL)
		outofmem(__FILE__, "HTSACat");
	} else {
	    if ((t = typecalloc(bstring)) == NULL)
		outofmem(__FILE__, "HTSACat");
	    t->str = (char *)malloc(need);
	}
	if (t->str == NULL)
	    outofmem(__FILE__, "HTSACat");
	memcpy (t->str + t->len, src, len);
	t->len += len;
	t->str[t->len] = '\0';
	*dest = t;
    }
    if (TRACE_BSTRING) {
	CTRACE((tfp, "=>     %4d:", BStrLen(*dest)));
	trace_bstring(*dest);
	CTRACE((tfp, "\n"));
    }
}

/*
 * Append a null-terminated string (discards the null).
 */
PUBLIC void HTSABCat0 ARGS2(
	bstring**,	dest,
	CONST char *,	src)
{
    HTSABCat(dest, src, strlen(src));
}

/*
 * Compare two bstring's for equality
 */
PUBLIC BOOL HTSABEql   ARGS2(
	bstring *,	a,
	bstring *,	b)
{
    unsigned len_a = (a != 0) ? a->len : 0;
    unsigned len_b = (b != 0) ? b->len : 0;

    if (len_a == len_b) {
	if (len_a == 0
	 || memcmp(a->str, b->str, a->len) == 0)
	    return TRUE;
    }
    return FALSE;
}

/*
 * Deallocate a bstring.
 */
PUBLIC void HTSABFree ARGS1(
	bstring **,	ptr)
{
    if (*ptr != NULL) {
	FREE((*ptr)->str);
	FREE(*ptr);
	*ptr = NULL;
    }
}

/*
 * Use this function to perform formatted sprintf's onto the end of a bstring.
 * The bstring may contain embedded nulls; the formatted portions must not.
 */
#ifdef ANSI_VARARGS
PUBLIC bstring * HTBprintf (bstring ** pstr, CONST char * fmt, ...)
#else
PUBLIC bstring * HTBprintf (va_alist)
    va_dcl
#endif
{
    bstring *result = 0;
    char *temp = 0;
    va_list ap;

    LYva_start(ap,fmt);
    {
#if !ANSI_VARARGS
	bstring **	pstr = va_arg(ap, char **);
	CONST char *	fmt  = va_arg(ap, CONST char *);
#endif
	temp = StrAllocVsprintf(&temp, 0, fmt, &ap);
	if (!isEmpty(temp)) {
	    HTSABCat (pstr, temp, strlen(temp));
	}
	FREE(temp);
	result = *pstr;
    }
    va_end(ap);

    return (result);
}

/*
 * Write binary-data to the logfile, making it safe for most editors to view.
 * That is most, since we do not restrict line-length.  Nulls and other
 * non-printing characters are addressed.
 */
PUBLIC void trace_bstring2 ARGS2(
	CONST char *,	text,
	int,		size)
{
    int n;

    if (text != 0) {
	for (n = 0; n < size; ++n) {
	    int ch = UCH(text[n]);
	    switch (ch) {
	    case '\\':
		fputs("\\\\", tfp);
		break;
	    case '\r':
		fputs("\\r", tfp);
		break;
	    case '\t':
		fputs("\\t", tfp);
		break;
	    case '\f':
		fputs("\\f", tfp);
		break;
	    default:
		if (isprint(ch) || isspace(ch)) {
		    fputc(ch, tfp);
		} else {
		    fprintf(tfp, "\\%03o", ch);
		}
		break;
	    }
	}
    }
}

PUBLIC void trace_bstring ARGS1(
	bstring *,	data)
{
    trace_bstring2(BStrData(data), BStrLen(data));
}