/*-------------------------------------------------------------------------
*
- * char.c--
- * Functions for the built-in type "char".
- * Functions for the built-in type "cid".
- * Functions for the built-in type "char2".
- * Functions for the built-in type "char4".
- * Functions for the built-in type "char8".
- * Functions for the built-in type "char16".
+ * char.c
+ * Functions for the built-in type "char" (not to be confused with
+ * bpchar, which is the SQL CHAR(n) type).
*
- * Copyright (c) 1994, Regents of the University of California
+ * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
*
*
* IDENTIFICATION
- * $Header: /cvsroot/pgsql/src/backend/utils/adt/char.c,v 1.2 1996/09/10 06:41:34 scrappy Exp $
+ * src/backend/utils/adt/char.c
*
*-------------------------------------------------------------------------
*/
-#include <stdio.h> /* for sprintf() */
-#include <string.h>
#include "postgres.h"
-#include "utils/palloc.h"
-#include "utils/builtins.h" /* where the declarations go */
-/*****************************************************************************
- * USER I/O ROUTINES *
- *****************************************************************************/
+#include <limits.h>
-/*
- * charin - converts "x" to 'x'
- */
-int32 charin(char *ch)
-{
- if (ch == NULL)
- return((int32) NULL);
- return((int32) *ch);
-}
+#include "libpq/pqformat.h"
+#include "utils/builtins.h"
-/*
- * charout - converts 'x' to "x"
- */
-char *charout(int32 ch)
-{
- char *result = (char *) palloc(2);
-
- result[0] = (char) ch;
- result[1] = '\0';
- return(result);
-}
+/*****************************************************************************
+ * USER I/O ROUTINES *
+ *****************************************************************************/
/*
- * cidin - converts "..." to internal representation.
+ * charin - converts "x" to 'x'
*
- * NOTE: we must not use 'charin' because cid might be a non
- * printable character...
+ * Note that an empty input string will implicitly be converted to \0.
*/
-int32 cidin(char *s)
+Datum
+charin(PG_FUNCTION_ARGS)
{
- CommandId c;
-
- if (s==NULL)
- c = 0;
- else
- c = atoi(s);
-
- return((int32)c);
+ char *ch = PG_GETARG_CSTRING(0);
+
+ PG_RETURN_CHAR(ch[0]);
}
/*
- * cidout - converts a cid to "..."
+ * charout - converts 'x' to "x"
*
- * NOTE: we must no use 'charout' because cid might be a non
- * printable character...
+ * Note that if the char value is \0, the resulting string will appear
+ * to be empty (null-terminated after zero characters). So this is the
+ * inverse of the charin() function for such data.
*/
-char *cidout(int32 c)
+Datum
+charout(PG_FUNCTION_ARGS)
{
- char *result;
- CommandId c2;
-
- /*
- * cid is a number between 0 .. 2^16-1, therefore we need at most
- * 6 chars for the string (5 digits + '\0')
- * NOTE: print it as an UNSIGNED int!
- */
- result = palloc(6);
- c2 = (CommandId)c;
- sprintf(result, "%u", (unsigned)(c2));
- return(result);
+ char ch = PG_GETARG_CHAR(0);
+ char *result = (char *) palloc(2);
+
+ result[0] = ch;
+ result[1] = '\0';
+ PG_RETURN_CSTRING(result);
}
/*
- * char16in - converts "..." to internal reprsentation
+ * charrecv - converts external binary format to char
*
- * Note:
- * Currently if strlen(s) < 14, the extra chars are nulls
+ * The external representation is one byte, with no character set
+ * conversion. This is somewhat dubious, perhaps, but in many
+ * cases people use char for a 1-byte binary type.
*/
-char *char16in(char *s)
+Datum
+charrecv(PG_FUNCTION_ARGS)
{
- char *result;
-
- if (s == NULL)
- return(NULL);
- result = (char *) palloc(16);
- memset(result, 0, 16);
- (void) strncpy(result, s, 16);
- return(result);
+ StringInfo buf = (StringInfo) PG_GETARG_POINTER(0);
+
+ PG_RETURN_CHAR(pq_getmsgbyte(buf));
}
/*
- * char16out - converts internal reprsentation to "..."
+ * charsend - converts char to binary format
*/
-char *char16out(char *s)
+Datum
+charsend(PG_FUNCTION_ARGS)
{
- char *result = (char *) palloc(17);
-
- memset(result, 0, 17);
- if (s == NULL) {
- result[0] = '-';
- } else {
- strncpy(result, s, 16);
- }
- return(result);
-}
+ char arg1 = PG_GETARG_CHAR(0);
+ StringInfoData buf;
+ pq_begintypsend(&buf);
+ pq_sendbyte(&buf, arg1);
+ PG_RETURN_BYTEA_P(pq_endtypsend(&buf));
+}
-/*****************************************************************************
- * PUBLIC ROUTINES *
+/*****************************************************************************
+ * PUBLIC ROUTINES *
*****************************************************************************/
-int32 chareq(int8 arg1, int8 arg2) { return(arg1 == arg2); }
-int32 charne(int8 arg1, int8 arg2) { return(arg1 != arg2); }
-#ifdef UNSIGNED_CHAR_TEXT
-int32 charlt(int8 arg1, int8 arg2) { return((uint8)arg1 < (uint8)arg2); }
-int32 charle(int8 arg1, int8 arg2) { return((uint8)arg1 <= (uint8)arg2); }
-int32 chargt(int8 arg1, int8 arg2) { return((uint8)arg1 > (uint8)arg2); }
-int32 charge(int8 arg1, int8 arg2) { return((uint8)arg1 >= (uint8)arg2); }
-#else
-int32 charlt(int8 arg1, int8 arg2) { return(arg1 < arg2); }
-int32 charle(int8 arg1, int8 arg2) { return(arg1 <= arg2); }
-int32 chargt(int8 arg1, int8 arg2) { return(arg1 > arg2); }
-int32 charge(int8 arg1, int8 arg2) { return(arg1 >= arg2); }
-#endif
-int8 charpl(int8 arg1, int8 arg2) { return(arg1 + arg2); }
-int8 charmi(int8 arg1, int8 arg2) { return(arg1 - arg2); }
-int8 charmul(int8 arg1, int8 arg2) { return(arg1 * arg2); }
-int8 chardiv(int8 arg1, int8 arg2) { return(arg1 / arg2); }
-
-int32 cideq(int8 arg1, int8 arg2) { return(arg1 == arg2); }
-
/*
- * char16eq - returns 1 iff arguments are equal
- * char16ne - returns 1 iff arguments are not equal
- *
- * BUGS:
- * Assumes that "xy\0\0a" should be equal to "xy\0b".
- * If not, can do the comparison backwards for efficiency.
- *
- * char16lt - returns 1 iff a < b
- * char16le - returns 1 iff a <= b
- * char16gt - returns 1 iff a < b
- * char16ge - returns 1 iff a <= b
+ * NOTE: comparisons are done as though char is unsigned (uint8).
+ * Conversions to and from integer are done as though char is signed (int8).
*
+ * You wanted consistency?
*/
-int32 char16eq(char *arg1, char *arg2)
-{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
- return(strncmp(arg1, arg2, 16) == 0);
-}
-
-int32 char16ne(char *arg1, char *arg2)
-{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
- return(strncmp(arg1, arg2, 16) != 0);
-}
-
-int32 char16lt(char *arg1, char *arg2)
-{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
- return((int32) (strncmp(arg1, arg2, 16) < 0));
-}
-
-int32 char16le(char *arg1, char *arg2)
-{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
- return((int32) (strncmp(arg1, arg2, 16) <= 0));
-}
-
-int32 char16gt(char *arg1, char *arg2)
-{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
-
- return((int32) (strncmp(arg1, arg2, 16) > 0));
-}
-
-int32 char16ge(char *arg1, char *arg2)
-{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
-
- return((int32) (strncmp(arg1, arg2, 16) >= 0));
-}
-
-/* ============================== char2 ============================== */
-uint16 char2in(char *s)
+Datum
+chareq(PG_FUNCTION_ARGS)
{
- uint16 res;
-
- if (s == NULL)
- return(0);
-
- memset((char *) &res, 0, sizeof(res));
- (void) strncpy((char *) &res, s, 2);
- return(res);
-}
+ char arg1 = PG_GETARG_CHAR(0);
+ char arg2 = PG_GETARG_CHAR(1);
-char *char2out(uint16 s)
-{
- char *result = (char *) palloc(3);
-
- memset(result, 0, 3);
- (void) strncpy(result, (char *) &s, 2);
-
- return(result);
-}
-
-int32 char2eq(uint16 a, uint16 b)
-{
- return(strncmp((char *) &a, (char *) &b, 2) == 0);
+ PG_RETURN_BOOL(arg1 == arg2);
}
-int32 char2ne(uint16 a, uint16 b)
+Datum
+charne(PG_FUNCTION_ARGS)
{
- return(strncmp((char *) &a, (char *) &b, 2) != 0);
-}
-
-int32 char2lt(uint16 a, uint16 b)
-{
- return(strncmp((char *) &a, (char *) &b, 2) < 0);
-}
+ char arg1 = PG_GETARG_CHAR(0);
+ char arg2 = PG_GETARG_CHAR(1);
-int32 char2le(uint16 a, uint16 b)
-{
- return(strncmp((char *) &a, (char *) &b, 2) <= 0);
+ PG_RETURN_BOOL(arg1 != arg2);
}
-int32 char2gt(uint16 a, uint16 b)
+Datum
+charlt(PG_FUNCTION_ARGS)
{
- return(strncmp((char *) &a, (char *) &b, 2) > 0);
-}
+ char arg1 = PG_GETARG_CHAR(0);
+ char arg2 = PG_GETARG_CHAR(1);
-int32 char2ge(uint16 a, uint16 b)
-{
- return(strncmp((char *) &a, (char *) &b, 2) >= 0);
+ PG_RETURN_BOOL((uint8) arg1 < (uint8) arg2);
}
-int32 char2cmp(uint16 a, uint16 b)
+Datum
+charle(PG_FUNCTION_ARGS)
{
- return (strncmp((char *) &a, (char *) &b, 2));
-}
+ char arg1 = PG_GETARG_CHAR(0);
+ char arg2 = PG_GETARG_CHAR(1);
-/* ============================== char4 ============================== */
-uint32 char4in(char *s)
-{
- uint32 res;
-
- if (s == NULL)
- return(0);
-
- memset((char *) &res, 0, sizeof(res));
- (void) strncpy((char *) &res, s, 4);
-
- return(res);
+ PG_RETURN_BOOL((uint8) arg1 <= (uint8) arg2);
}
-char *char4out(s)
- uint32 s;
+Datum
+chargt(PG_FUNCTION_ARGS)
{
- char *result = (char *) palloc(5);
-
- memset(result, 0, 5);
- (void) strncpy(result, (char *) &s, 4);
-
- return(result);
-}
+ char arg1 = PG_GETARG_CHAR(0);
+ char arg2 = PG_GETARG_CHAR(1);
-int32 char4eq(uint32 a, uint32 b)
-{
- return(strncmp((char *) &a, (char *) &b, 4) == 0);
+ PG_RETURN_BOOL((uint8) arg1 > (uint8) arg2);
}
-int32 char4ne(uint32 a, uint32 b)
+Datum
+charge(PG_FUNCTION_ARGS)
{
- return(strncmp((char *) &a, (char *) &b, 4) != 0);
-}
+ char arg1 = PG_GETARG_CHAR(0);
+ char arg2 = PG_GETARG_CHAR(1);
-int32 char4lt(uint32 a, uint32 b)
-{
- return(strncmp((char *) &a, (char *) &b, 4) < 0);
+ PG_RETURN_BOOL((uint8) arg1 >= (uint8) arg2);
}
-int32 char4le(uint32 a, uint32 b)
-{
- return(strncmp((char *) &a, (char *) &b, 4) <= 0);
-}
-int32 char4gt(uint32 a, uint32 b)
+Datum
+chartoi4(PG_FUNCTION_ARGS)
{
- return(strncmp((char *) &a, (char *) &b, 4) > 0);
-}
+ char arg1 = PG_GETARG_CHAR(0);
-int32 char4ge(uint32 a, uint32 b)
-{
- return(strncmp((char *) &a, (char *) &b, 4) >= 0);
+ PG_RETURN_INT32((int32) ((int8) arg1));
}
-int32 char4cmp(uint32 a, uint32 b)
+Datum
+i4tochar(PG_FUNCTION_ARGS)
{
- return(strncmp((char *) &a, (char *) &b, 4));
-}
+ int32 arg1 = PG_GETARG_INT32(0);
-/* ============================== char8 ============================== */
-char *char8in(char *s)
-{
- char *result;
-
- if (s == NULL)
- return((char *) NULL);
-
- result = (char *) palloc(8);
- memset(result, 0, 8);
- (void) strncpy(result, s, 8);
- return(result);
-}
+ if (arg1 < SCHAR_MIN || arg1 > SCHAR_MAX)
+ ereport(ERROR,
+ (errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
+ errmsg("\"char\" out of range")));
-char *char8out(char *s)
-{
- char *result = (char *) palloc(9);
-
- memset(result, 0, 9);
- if (s == NULL) {
- result[0] = '-';
- } else {
- strncpy(result, s, 8);
- }
- return(result);
+ PG_RETURN_CHAR((int8) arg1);
}
-int32 char8eq(char *arg1, char *arg2)
-{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
- return(strncmp(arg1, arg2, 8) == 0);
-}
-int32 char8ne(char *arg1, char *arg2)
+Datum
+text_char(PG_FUNCTION_ARGS)
{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
- return(strncmp(arg1, arg2, 8) != 0);
-}
+ text *arg1 = PG_GETARG_TEXT_PP(0);
+ char result;
-int32 char8lt(char *arg1, char *arg2)
-{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
- return(strncmp(arg1, arg2, 8) < 0);
-}
+ /*
+ * An empty input string is converted to \0 (for consistency with charin).
+ * If the input is longer than one character, the excess data is silently
+ * discarded.
+ */
+ if (VARSIZE_ANY_EXHDR(arg1) > 0)
+ result = *(VARDATA_ANY(arg1));
+ else
+ result = '\0';
-int32 char8le(char *arg1, char *arg2)
-{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
- return(strncmp(arg1, arg2, 8) <= 0);
+ PG_RETURN_CHAR(result);
}
-int32 char8gt(char *arg1, char *arg2)
+Datum
+char_text(PG_FUNCTION_ARGS)
{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
- return(strncmp(arg1, arg2, 8) > 0);
-}
+ char arg1 = PG_GETARG_CHAR(0);
+ text *result = palloc(VARHDRSZ + 1);
-int32 char8ge(char *arg1, char *arg2)
-{
- if (arg1 == NULL || arg2 == NULL)
- return((int32) 0);
- return(strncmp(arg1, arg2, 8) >= 0);
-}
+ /*
+ * Convert \0 to an empty string, for consistency with charout (and
+ * because the text stuff doesn't like embedded nulls all that well).
+ */
+ if (arg1 != '\0')
+ {
+ SET_VARSIZE(result, VARHDRSZ + 1);
+ *(VARDATA(result)) = arg1;
+ }
+ else
+ SET_VARSIZE(result, VARHDRSZ);
-int32 char8cmp(char *arg1, char *arg2)
-{
- return(strncmp(arg1, arg2, 8));
+ PG_RETURN_TEXT_P(result);
}
projects / postgresql / blobdiff