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	of the array constants and in one of the loadable modules I posted some time ago. Submitted by: Massimo Dal Zotto <dz@cs.unitn.it>
		
			
				
	
	
		
			362 lines
		
	
	
		
			6.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			362 lines
		
	
	
		
			6.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * string_io.c --
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|  *
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|  * This file defines new input/output conversion routines for strings.
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|  *
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|  * Copyright (c) 1996, Massimo Dal Zotto <dz@cs.unitn.it>
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|  */
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| 
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| #include <ctype.h>
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| #include <string.h>
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| 
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| #include "postgres.h"
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| #include "utils/elog.h"
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| #include "utils/palloc.h"
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| #include "utils/builtins.h"
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| 
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| /* define this if you want to see iso-8859 characters */
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| #define ISO8859
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| 
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| #define MIN(x, y)	((x) < (y) ? (x) : (y))
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| #define	VALUE(char) 	((char) - '0')
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| #define	DIGIT(val)	((val) + '0')
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| #define ISOCTAL(c) 	(((c) >= '0') && ((c) <= '7'))
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| #ifndef ISO8859
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| #define NOTPRINTABLE(c)	(!isprint(c))
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| #else
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| #define NOTPRINTABLE(c)	(!isprint(c) && ((c) < 0xa0))
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| #endif
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| 
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| /*
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|  * string_output() --
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|  *
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|  * This function takes a pointer to a string data and an optional
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|  * data size and returns a printable representation of the data
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|  * translating all escape sequences to C-like \nnn or \c escapes.
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|  * The function is used by output methods of various string types.
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|  *
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|  * Arguments:
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|  *	data -		input data (can be NULL)
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|  *	size -		optional size of data. A negative value indicates
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|  *			that data is a null terminated string.
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|  *
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|  * Returns:
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|  *	a pointer to a new string containing the printable
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|  *	representation of data.
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|  */
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| 
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| char *
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| string_output(char *data, int size)
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| {
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|     register unsigned char c, *p, *r, *result;
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|     register int l, len;
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| 
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|     if (data == NULL) {
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| 	result = (char *) palloc(2);
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| 	result[0] = '-';
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| 	result[1] = '\0';
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| 	return (result);
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|     }
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| 
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|     if (size < 0) {
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| 	size = strlen(data);
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|     }
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| 
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|     /* adjust string length for escapes */
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|     len = size;
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|     for (p=data,l=size; l>0; p++,l--) {
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| 	switch (*p) {
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| 	  case '\\':
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| 	  case '"' :
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| 	  case '{':
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| 	  case '}':
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| 	  case '\b':
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| 	  case '\f':
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| 	  case '\n':
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| 	  case '\r':
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| 	  case '\t':
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| 	  case '\v':
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| 	    len++;
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| 	    break;
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| 	  default:
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| 	    if (NOTPRINTABLE(*p)) {
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| 		len += 3;
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| 	    }
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| 	}
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|     }
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|     len++;
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| 
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|     result = (char *) palloc(len);
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| 
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|     for (p=data,r=result,l=size; (l > 0) && (c = *p); p++,l--) {
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| 	switch (c) {
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| 	  case '\\':
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| 	  case '"' :
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| 	  case '{':
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| 	  case '}':
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| 	    *r++ = '\\';
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| 	    *r++ = c;
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| 	    break;
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| 	  case '\b':
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| 	    *r++ = '\\';
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| 	    *r++ = 'b';
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| 	    break;
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| 	  case '\f':
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| 	    *r++ = '\\';
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| 	    *r++ = 'f';
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| 	    break;
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| 	  case '\n':
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| 	    *r++ = '\\';
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| 	    *r++ = 'n';
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| 	    break;
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| 	  case '\r':
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| 	    *r++ = '\\';
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| 	    *r++ = 'r';
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| 	    break;
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| 	  case '\t':
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| 	    *r++ = '\\';
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| 	    *r++ = 't';
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| 	    break;
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| 	  case '\v':
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| 	    *r++ = '\\';
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| 	    *r++ = 'v';
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| 	    break;
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| 	  default:
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| 	    if (NOTPRINTABLE(c)) {
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| 		*r = '\\';
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| 		r += 3;
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| 		*r-- = DIGIT(c & 07);
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| 		c >>= 3;
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| 		*r-- = DIGIT(c & 07);
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| 		c >>= 3;
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| 		*r   = DIGIT(c & 03);
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| 		r += 3;
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| 	    } else {
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| 		*r++ = c;
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| 	    }
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| 	}
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|     }
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|     *r = '\0';
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| 
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|     return((char *) result);
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| }
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| 
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| /*
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|  * string_input() --
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|  *
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|  * This function accepts a C string in input and copies it into a new 
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|  * object allocated with palloc() translating all escape sequences.
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|  * An optional header can be allocatd before the string, for example
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|  * to hold the length of a varlena object.
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|  * This function is not necessary for input from sql commands because
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|  * the parser already does escape translation, all data input routines
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|  * receive strings in internal form.
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|  *
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|  * Arguments:
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|  *	str -		input string possibly with escapes
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|  *	size -		the required size of new data. A value of 0
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|  *			indicates a variable size string, while a
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|  *			negative value indicates a variable size string
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|  *			of size not greater than this absolute value.
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|  *	hdrsize -	size of an optional header to be allocated before
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|  *			the data. It must then be filled by the caller.
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|  *	rtn_size -	an optional pointer to an int variable where the
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|  *			size of the new string is stored back.
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|  *
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|  * Returns:
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|  *	a pointer to the new string or the header.
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|  */
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| 
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| char *
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| string_input(char *str, int size, int hdrsize, int *rtn_size)
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| {
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|     register unsigned char *p, *r;
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|     unsigned char *result;
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|     int len;
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| 
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|     if ((str == NULL) || (hdrsize < 0)) {
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| 	return (char *) NULL;
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|     }
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| 
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|     /* Compute result size */
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|     len = strlen(str);
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|     for (p=str; *p; ) {
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| 	if (*p++ == '\\') {
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| 	    if (ISOCTAL(*p)) {
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| 		if (ISOCTAL(*(p+1))) {
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| 		    p++;
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| 		    len--;
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| 		}
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| 		if (ISOCTAL(*(p+1))) {
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| 		    p++;
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| 		    len--;
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| 		}
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| 	    }
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| 	    if (*p) p++;
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| 	    len--;
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| 	}
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|     }
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| 
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|     /* result has variable length */
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|     if (size == 0) {
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| 	size = len+1;
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|     } else
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| 
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|     /* result has variable length with maximum size */
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|     if (size < 0) {
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| 	size = MIN(len, - size)+1;
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|     }
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| 
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|     result = (char *) palloc(hdrsize+size);
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|     memset(result, 0, hdrsize+size);
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|     if (rtn_size) {
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| 	*rtn_size = size;
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|     }
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| 
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|     r = result + hdrsize;
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|     for (p=str; *p; ) {
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| 	register unsigned char c;
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| 	if ((c = *p++) == '\\') {
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| 	    switch (c = *p++) {
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| 	      case '\0':
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| 		p--;
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| 		break;
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| 	      case '0':
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| 	      case '1':
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| 	      case '2':
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| 	      case '3':
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| 	      case '4':
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| 	      case '5':
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| 	      case '6':
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| 	      case '7':
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| 		c = VALUE(c);
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| 		if (isdigit(*p)) {
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| 		    c = (c<<3) + VALUE(*p++);
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| 		}
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| 		if (isdigit(*p)) {
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| 		    c = (c<<3) + VALUE(*p++);
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| 		}
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| 		*r++ = c;
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| 		break;
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| 	      case 'b':
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| 		*r++ = '\b';
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| 		break;
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| 	      case 'f':
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| 		*r++ = '\f';
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| 		break;
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| 	      case 'n':
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| 		*r++ = '\n';
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| 		break;
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| 	      case 'r':
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| 		*r++ = '\r';
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| 		break;
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| 	      case 't':
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| 		*r++ = '\t';
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| 		break;
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| 	      case 'v':
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| 		*r++ = '\v';
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| 		break;
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| 	      default:
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| 		*r++ = c;
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| 	    }
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| 	} else {
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| 	    *r++ = c;
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| 	}
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|     }
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| 
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|     return((char *) result);
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| }
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| 
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| char *
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| c_charout(int32 c)
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| {
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|     char str[2];
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| 
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|     str[0] = (char) c;
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|     str[1] = '\0';
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| 
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|     return (string_output(str, 1));
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| }
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| 
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| char *
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| c_char2out(uint16 s)
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| {
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|     return (string_output((char *) &s, 2));
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| }
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| 
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| char *
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| c_char4out(uint32 s)
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| {
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|     return (string_output((char *) &s, 4));
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| }
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| 
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| char *
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| c_char8out(char *s)
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| {
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|     return (string_output(s, 8));
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| }
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| 
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| char *
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| c_char16out(char *s)
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| {
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|     return (string_output(s, 16));
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| }
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| 
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| /*
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|  * This can be used for text, bytea, SET and unknown data types
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|  */
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| 
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| char *
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| c_textout(struct varlena *vlena)
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| {
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|     int len = 0;
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|     char *s = NULL;
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| 
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|     if (vlena) {
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| 	len = VARSIZE(vlena) - VARHDRSZ;
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| 	s = VARDATA(vlena);
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|     }
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|     return (string_output(s, len));
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| }
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| 
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| /*
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|  * This can be used for varchar and bpchar strings
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|  */
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| 
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| char *
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| c_varcharout(char *s)
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| {
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|     int len;
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| 
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|     if (s) {
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| 	len = *(int32*)s - 4;
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| 	s += 4;
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|     }
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|     return (string_output(s, len));
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| }
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| 
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| #ifdef 0
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| struct varlena *
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| c_textin(char *str)
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| {
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|     struct varlena *result;
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|     int len;
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| 
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|     if (str == NULL) {
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| 	return ((struct varlena *) NULL);
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|     }
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| 
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|     result = (struct varlena *) string_input(str, 0, VARHDRSZ, &len);
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|     VARSIZE(result) = len;
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| 
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|     return (result);
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| }
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| 
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| char *
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| c_char16in(char *str)
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| {
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|     return (string_input(str, 16, 0, NULL));
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| }
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| #endif
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| 
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