Make NUM_TOCHAR_prepare and NUM_TOCHAR_finish macros declare "len".

Remove the variable from the enclosing scopes so that nothing can be
relying on it.  The net result of this refactoring is that we get rid
of a few unnecessary strlen() calls.

Original patch from Greg Jaskiewicz, substantially expanded by me.

diff --git a/src/backend/utils/adt/formatting.c b/src/backend/utils/adt/formatting.c
index 36353c39c16dab0254101cb9a840307d5d4751f1..946f3e28c651b1a317e9b126bb1d871928de2758 100644 (file)
--- a/src/backend/utils/adt/formatting.c
+++ b/src/backend/utils/adt/formatting.c
@@ -4877,7 +4877,7 @@ NUM_processor(FormatNode *node, NUMDesc *Num, char *inout, char *number,
  */
 #define NUM_TOCHAR_prepare \
 do { \
-   len = VARSIZE_ANY_EXHDR(fmt); \
+   int len = VARSIZE_ANY_EXHDR(fmt); \
    if (len <= 0 || len >= (INT_MAX-VARHDRSZ)/NUM_MAX_ITEM_SIZ)     \
        PG_RETURN_TEXT_P(cstring_to_text("")); \
    result  = (text *) palloc0((len * NUM_MAX_ITEM_SIZ) + 1 + VARHDRSZ);    \
@@ -4890,6 +4890,8 @@ do { \
  */
 #define NUM_TOCHAR_finish \
 do { \
+   int     len; \
+                                   \
    NUM_processor(format, &Num, VARDATA(result), numstr, plen, sign, true, PG_GET_COLLATION()); \
                                    \
    if (shouldFree)                 \
@@ -4961,8 +4963,7 @@ numeric_to_char(PG_FUNCTION_ARGS)
    FormatNode *format;
    text       *result;
    bool        shouldFree;
-   int         len = 0,
-               plen = 0,
+   int         plen = 0,
                sign = 0;
    char       *numstr,
               *orgnum,
@@ -5008,16 +5009,15 @@ numeric_to_char(PG_FUNCTION_ARGS)
            numstr = (char *) palloc(strlen(orgnum) + 2);
            *numstr = ' ';
            strcpy(numstr + 1, orgnum);
-           len = strlen(numstr);
        }
        else
        {
            numstr = orgnum;
-           len = strlen(orgnum);
        }
    }
    else
    {
+       int         len;
        Numeric     val = value;
 
        if (IS_MULTI(&Num))
@@ -5084,8 +5084,7 @@ int4_to_char(PG_FUNCTION_ARGS)
    FormatNode *format;
    text       *result;
    bool        shouldFree;
-   int         len = 0,
-               plen = 0,
+   int         plen = 0,
                sign = 0;
    char       *numstr,
               *orgnum;
@@ -5111,11 +5110,12 @@ int4_to_char(PG_FUNCTION_ARGS)
        if (*orgnum == '+')
            *orgnum = ' ';
 
-       len = strlen(orgnum);
        numstr = orgnum;
    }
    else
    {
+       int         len;
+
        if (IS_MULTI(&Num))
        {
            orgnum = DatumGetCString(DirectFunctionCall1(int4out,
@@ -5175,8 +5175,7 @@ int8_to_char(PG_FUNCTION_ARGS)
    FormatNode *format;
    text       *result;
    bool        shouldFree;
-   int         len = 0,
-               plen = 0,
+   int         plen = 0,
                sign = 0;
    char       *numstr,
               *orgnum;
@@ -5211,16 +5210,16 @@ int8_to_char(PG_FUNCTION_ARGS)
            numstr = (char *) palloc(strlen(orgnum) + 2);
            *numstr = ' ';
            strcpy(numstr + 1, orgnum);
-           len = strlen(numstr);
        }
        else
        {
            numstr = orgnum;
-           len = strlen(orgnum);
        }
    }
    else
    {
+       int         len;
+
        if (IS_MULTI(&Num))
        {
            double      multi = pow((double) 10, (double) Num.multi);
@@ -5282,8 +5281,7 @@ float4_to_char(PG_FUNCTION_ARGS)
    FormatNode *format;
    text       *result;
    bool        shouldFree;
-   int         len = 0,
-               plen = 0,
+   int         plen = 0,
                sign = 0;
    char       *numstr,
               *orgnum,
@@ -5317,13 +5315,13 @@ float4_to_char(PG_FUNCTION_ARGS)
            if (*orgnum == '+')
                *orgnum = ' ';
 
-           len = strlen(orgnum);
            numstr = orgnum;
        }
    }
    else
    {
        float4      val = value;
+       int         len;
 
        if (IS_MULTI(&Num))
        {
@@ -5386,8 +5384,7 @@ float8_to_char(PG_FUNCTION_ARGS)
    FormatNode *format;
    text       *result;
    bool        shouldFree;
-   int         len = 0,
-               plen = 0,
+   int         plen = 0,
                sign = 0;
    char       *numstr,
               *orgnum,
@@ -5421,13 +5418,13 @@ float8_to_char(PG_FUNCTION_ARGS)
            if (*orgnum == '+')
                *orgnum = ' ';
 
-           len = strlen(orgnum);
            numstr = orgnum;
        }
    }
    else
    {
        float8      val = value;
+       int         len;
 
        if (IS_MULTI(&Num))
        {