Rename C variables in formatting.c, for clarity

Also add C comments.  This should help future debugging of this
notorious file.

diff --git a/src/backend/utils/adt/formatting.c b/src/backend/utils/adt/formatting.c
index e14d7bcc1319c1585b7509b89e7fc5752004ce6d..d5ff246c7bd4059ccd67656d2faa618262c7f2c1 100644 (file)
--- a/src/backend/utils/adt/formatting.c
+++ b/src/backend/utils/adt/formatting.c
@@ -917,7 +917,7 @@ typedef struct NUMProc
                num_count,      /* number of write digits   */
                num_in,         /* is inside number     */
                num_curr,       /* current position in number   */
-               num_pre,        /* space before first number    */
+               out_pre_spaces, /* spaces before first digit    */
 
                read_dec,       /* to_number - was read dec. point  */
                read_post,      /* to_number - number of dec. digit */
@@ -975,10 +975,11 @@ static FormatNode *NUM_cache(int len, NUMDesc *Num, text *pars_str, bool *should
 static char *int_to_roman(int number);
 static void NUM_prepare_locale(NUMProc *Np);
 static char *get_last_relevant_decnum(char *num);
-static void NUM_numpart_from_char(NUMProc *Np, int id, int plen);
+static void NUM_numpart_from_char(NUMProc *Np, int id, int input_len);
 static void NUM_numpart_to_char(NUMProc *Np, int id);
-static char *NUM_processor(FormatNode *node, NUMDesc *Num, char *inout, char *number,
-             int plen, int sign, bool is_to_char, Oid collid);
+static char *NUM_processor(FormatNode *node, NUMDesc *Num, char *inout,
+             char *number, int from_char_input_len, int to_char_out_pre_spaces,
+             int sign, bool is_to_char, Oid collid);
 static DCHCacheEntry *DCH_cache_search(char *str);
 static DCHCacheEntry *DCH_cache_getnew(char *str);
 
@@ -4054,7 +4055,7 @@ get_last_relevant_decnum(char *num)
  * ----------
  */
 static void
-NUM_numpart_from_char(NUMProc *Np, int id, int plen)
+NUM_numpart_from_char(NUMProc *Np, int id, int input_len)
 {
    bool        isread = FALSE;
 
@@ -4066,8 +4067,8 @@ NUM_numpart_from_char(NUMProc *Np, int id, int plen)
    if (*Np->inout_p == ' ')
        Np->inout_p++;
 
-#define OVERLOAD_TEST  (Np->inout_p >= Np->inout + plen)
-#define AMOUNT_TEST(_s) (plen-(Np->inout_p-Np->inout) >= _s)
+#define OVERLOAD_TEST  (Np->inout_p >= Np->inout + input_len)
+#define AMOUNT_TEST(_s) (input_len-(Np->inout_p-Np->inout) >= _s)
 
    if (*Np->inout_p == ' ')
        Np->inout_p++;
@@ -4206,7 +4207,7 @@ NUM_numpart_from_char(NUMProc *Np, int id, int plen)
         * next char is not digit
         */
        if (IS_LSIGN(Np->Num) && isread &&
-           (Np->inout_p + 1) <= Np->inout + plen &&
+           (Np->inout_p + 1) <= Np->inout + input_len &&
            !isdigit((unsigned char) *(Np->inout_p + 1)))
        {
            int         x;
@@ -4301,7 +4302,7 @@ NUM_numpart_to_char(NUMProc *Np, int id)
     * handle "9.9" --> " .1"
     */
    if (Np->sign_wrote == FALSE &&
-       (Np->num_curr >= Np->num_pre || (IS_ZERO(Np->Num) && Np->Num->zero_start == Np->num_curr)) &&
+       (Np->num_curr >= Np->out_pre_spaces || (IS_ZERO(Np->Num) && Np->Num->zero_start == Np->num_curr)) &&
        (IS_PREDEC_SPACE(Np) == FALSE || (Np->last_relevant && *Np->last_relevant == '.')))
    {
        if (IS_LSIGN(Np->Num))
@@ -4345,7 +4346,7 @@ NUM_numpart_to_char(NUMProc *Np, int id)
     */
    if (id == NUM_9 || id == NUM_0 || id == NUM_D || id == NUM_DEC)
    {
-       if (Np->num_curr < Np->num_pre &&
+       if (Np->num_curr < Np->out_pre_spaces &&
            (Np->Num->zero_start > Np->num_curr || !IS_ZERO(Np->Num)))
        {
            /*
@@ -4358,7 +4359,7 @@ NUM_numpart_to_char(NUMProc *Np, int id)
            }
        }
        else if (IS_ZERO(Np->Num) &&
-                Np->num_curr < Np->num_pre &&
+                Np->num_curr < Np->out_pre_spaces &&
                 Np->Num->zero_start <= Np->num_curr)
        {
            /*
@@ -4430,7 +4431,7 @@ NUM_numpart_to_char(NUMProc *Np, int id)
            ++Np->number_p;
        }
 
-       end = Np->num_count + (Np->num_pre ? 1 : 0) + (IS_DECIMAL(Np->Num) ? 1 : 0);
+       end = Np->num_count + (Np->out_pre_spaces ? 1 : 0) + (IS_DECIMAL(Np->Num) ? 1 : 0);
 
        if (Np->last_relevant && Np->last_relevant == Np->number_p)
            end = Np->num_curr;
@@ -4456,13 +4457,10 @@ NUM_numpart_to_char(NUMProc *Np, int id)
    ++Np->num_curr;
 }
 
-/*
- * Note: 'plen' is used in FROM_CHAR conversion and it's length of
- * input (inout). In TO_CHAR conversion it's space before first number.
- */
 static char *
-NUM_processor(FormatNode *node, NUMDesc *Num, char *inout, char *number,
-             int plen, int sign, bool is_to_char, Oid collid)
+NUM_processor(FormatNode *node, NUMDesc *Num, char *inout,
+             char *number, int from_char_input_len, int to_char_out_pre_spaces,
+             int sign, bool is_to_char, Oid collid)
 {
    FormatNode *n;
    NUMProc     _Np,
@@ -4502,7 +4500,7 @@ NUM_processor(FormatNode *node, NUMDesc *Num, char *inout, char *number,
                     errmsg("\"RN\" not supported for input")));
 
        Np->Num->lsign = Np->Num->pre_lsign_num = Np->Num->post =
-           Np->Num->pre = Np->num_pre = Np->sign = 0;
+           Np->Num->pre = Np->out_pre_spaces = Np->sign = 0;
 
        if (IS_FILLMODE(Np->Num))
        {
@@ -4560,7 +4558,7 @@ NUM_processor(FormatNode *node, NUMDesc *Num, char *inout, char *number,
 
    if (is_to_char)
    {
-       Np->num_pre = plen;
+       Np->out_pre_spaces = to_char_out_pre_spaces;
 
        if (IS_FILLMODE(Np->Num) && IS_DECIMAL(Np->Num))
        {
@@ -4570,22 +4568,22 @@ NUM_processor(FormatNode *node, NUMDesc *Num, char *inout, char *number,
             * If any '0' specifiers are present, make sure we don't strip
             * those digits.
             */
-           if (Np->last_relevant && Np->Num->zero_end > Np->num_pre)
+           if (Np->last_relevant && Np->Num->zero_end > Np->out_pre_spaces)
            {
                char       *last_zero;
 
-               last_zero = Np->number + (Np->Num->zero_end - Np->num_pre);
+               last_zero = Np->number + (Np->Num->zero_end - Np->out_pre_spaces);
                if (Np->last_relevant < last_zero)
                    Np->last_relevant = last_zero;
            }
        }
 
-       if (Np->sign_wrote == FALSE && Np->num_pre == 0)
+       if (Np->sign_wrote == FALSE && Np->out_pre_spaces == 0)
            ++Np->num_count;
    }
    else
    {
-       Np->num_pre = 0;
+       Np->out_pre_spaces = 0;
        *Np->number = ' ';      /* sign space */
        *(Np->number + 1) = '\0';
    }
@@ -4601,7 +4599,7 @@ NUM_processor(FormatNode *node, NUMDesc *Num, char *inout, char *number,
         Np->Num->pre,
         Np->Num->post,
         Np->num_count,
-        Np->num_pre,
+        Np->out_pre_spaces,
         Np->sign_wrote ? "Yes" : "No",
         IS_ZERO(Np->Num) ? "Yes" : "No",
         Np->Num->zero_start,
@@ -4636,7 +4634,7 @@ NUM_processor(FormatNode *node, NUMDesc *Num, char *inout, char *number,
            /*
             * Check non-string inout end
             */
-           if (Np->inout_p >= Np->inout + plen)
+           if (Np->inout_p >= Np->inout + from_char_input_len)
                break;
        }
 
@@ -4666,7 +4664,7 @@ NUM_processor(FormatNode *node, NUMDesc *Num, char *inout, char *number,
                    }
                    else
                    {
-                       NUM_numpart_from_char(Np, n->key->id, plen);
+                       NUM_numpart_from_char(Np, n->key->id, from_char_input_len);
                        break;  /* switch() case: */
                    }
 
@@ -4891,7 +4889,7 @@ do { \
 do { \
    int     len; \
                                    \
-   NUM_processor(format, &Num, VARDATA(result), numstr, plen, sign, true, PG_GET_COLLATION()); \
+   NUM_processor(format, &Num, VARDATA(result), numstr, 0, out_pre_spaces, sign, true, PG_GET_COLLATION()); \
                                    \
    if (shouldFree)                 \
        pfree(format);              \
@@ -4933,7 +4931,7 @@ numeric_to_number(PG_FUNCTION_ARGS)
    numstr = (char *) palloc((len * NUM_MAX_ITEM_SIZ) + 1);
 
    NUM_processor(format, &Num, VARDATA(value), numstr,
-                 VARSIZE(value) - VARHDRSZ, 0, false, PG_GET_COLLATION());
+                 VARSIZE(value) - VARHDRSZ, 0, 0, false, PG_GET_COLLATION());
 
    scale = Num.post;
    precision = Max(0, Num.pre) + scale;
@@ -4962,7 +4960,7 @@ numeric_to_char(PG_FUNCTION_ARGS)
    FormatNode *format;
    text       *result;
    bool        shouldFree;
-   int         plen = 0,
+   int         out_pre_spaces = 0,
                sign = 0;
    char       *numstr,
               *orgnum,
@@ -5016,7 +5014,7 @@ numeric_to_char(PG_FUNCTION_ARGS)
    }
    else
    {
-       int         len;
+       int         numstr_pre_len;
        Numeric     val = value;
 
        if (IS_MULTI(&Num))
@@ -5051,14 +5049,17 @@ numeric_to_char(PG_FUNCTION_ARGS)
            sign = '+';
            numstr = orgnum;
        }
+
        if ((p = strchr(numstr, '.')))
-           len = p - numstr;
+           numstr_pre_len = p - numstr;
        else
-           len = strlen(numstr);
+           numstr_pre_len = strlen(numstr);
 
-       if (Num.pre > len)
-           plen = Num.pre - len;
-       else if (len > Num.pre)
+       /* needs padding? */
+       if (numstr_pre_len < Num.pre)
+           out_pre_spaces = Num.pre - numstr_pre_len;
+       /* overflowed prefix digit format? */
+       else if (numstr_pre_len > Num.pre)
        {
            numstr = (char *) palloc(Num.pre + Num.post + 2);
            fill_str(numstr, '#', Num.pre + Num.post + 1);
@@ -5083,7 +5084,7 @@ int4_to_char(PG_FUNCTION_ARGS)
    FormatNode *format;
    text       *result;
    bool        shouldFree;
-   int         plen = 0,
+   int         out_pre_spaces = 0,
                sign = 0;
    char       *numstr,
               *orgnum;
@@ -5113,7 +5114,7 @@ int4_to_char(PG_FUNCTION_ARGS)
    }
    else
    {
-       int         len;
+       int         numstr_pre_len;
 
        if (IS_MULTI(&Num))
        {
@@ -5134,22 +5135,26 @@ int4_to_char(PG_FUNCTION_ARGS)
        }
        else
            sign = '+';
-       len = strlen(orgnum);
 
+       numstr_pre_len = strlen(orgnum);
+
+       /* post-decimal digits?  Pad out with zeros. */
        if (Num.post)
        {
-           numstr = (char *) palloc(len + Num.post + 2);
+           numstr = (char *) palloc(numstr_pre_len + Num.post + 2);
            strcpy(numstr, orgnum);
-           *(numstr + len) = '.';
-           memset(numstr + len + 1, '0', Num.post);
-           *(numstr + len + Num.post + 1) = '\0';
+           *(numstr + numstr_pre_len) = '.';
+           memset(numstr + numstr_pre_len + 1, '0', Num.post);
+           *(numstr + numstr_pre_len + Num.post + 1) = '\0';
        }
        else
            numstr = orgnum;
 
-       if (Num.pre > len)
-           plen = Num.pre - len;
-       else if (len > Num.pre)
+       /* needs padding? */
+       if (numstr_pre_len < Num.pre)
+           out_pre_spaces = Num.pre - numstr_pre_len;
+       /* overflowed prefix digit format? */
+       else if (numstr_pre_len > Num.pre)
        {
            numstr = (char *) palloc(Num.pre + Num.post + 2);
            fill_str(numstr, '#', Num.pre + Num.post + 1);
@@ -5174,7 +5179,7 @@ int8_to_char(PG_FUNCTION_ARGS)
    FormatNode *format;
    text       *result;
    bool        shouldFree;
-   int         plen = 0,
+   int         out_pre_spaces = 0,
                sign = 0;
    char       *numstr,
               *orgnum;
@@ -5217,7 +5222,7 @@ int8_to_char(PG_FUNCTION_ARGS)
    }
    else
    {
-       int         len;
+       int         numstr_pre_len;
 
        if (IS_MULTI(&Num))
        {
@@ -5240,22 +5245,26 @@ int8_to_char(PG_FUNCTION_ARGS)
        }
        else
            sign = '+';
-       len = strlen(orgnum);
 
+       numstr_pre_len = strlen(orgnum);
+
+       /* post-decimal digits?  Pad out with zeros. */
        if (Num.post)
        {
-           numstr = (char *) palloc(len + Num.post + 2);
+           numstr = (char *) palloc(numstr_pre_len + Num.post + 2);
            strcpy(numstr, orgnum);
-           *(numstr + len) = '.';
-           memset(numstr + len + 1, '0', Num.post);
-           *(numstr + len + Num.post + 1) = '\0';
+           *(numstr + numstr_pre_len) = '.';
+           memset(numstr + numstr_pre_len + 1, '0', Num.post);
+           *(numstr + numstr_pre_len + Num.post + 1) = '\0';
        }
        else
            numstr = orgnum;
 
-       if (Num.pre > len)
-           plen = Num.pre - len;
-       else if (len > Num.pre)
+       /* needs padding? */
+       if (numstr_pre_len < Num.pre)
+           out_pre_spaces = Num.pre - numstr_pre_len;
+       /* overflowed prefix digit format? */
+       else if (numstr_pre_len > Num.pre)
        {
            numstr = (char *) palloc(Num.pre + Num.post + 2);
            fill_str(numstr, '#', Num.pre + Num.post + 1);
@@ -5280,7 +5289,7 @@ float4_to_char(PG_FUNCTION_ARGS)
    FormatNode *format;
    text       *result;
    bool        shouldFree;
-   int         plen = 0,
+   int         out_pre_spaces = 0,
                sign = 0;
    char       *numstr,
               *orgnum,
@@ -5320,7 +5329,7 @@ float4_to_char(PG_FUNCTION_ARGS)
    else
    {
        float4      val = value;
-       int         len;
+       int         numstr_pre_len;
 
        if (IS_MULTI(&Num))
        {
@@ -5332,13 +5341,13 @@ float4_to_char(PG_FUNCTION_ARGS)
 
        orgnum = (char *) palloc(MAXFLOATWIDTH + 1);
        snprintf(orgnum, MAXFLOATWIDTH + 1, "%.0f", fabs(val));
-       len = strlen(orgnum);
-       if (Num.pre > len)
-           plen = Num.pre - len;
-       if (len >= FLT_DIG)
+       numstr_pre_len = strlen(orgnum);
+
+       /* adjust post digits to fit max float digits */
+       if (numstr_pre_len >= FLT_DIG)
            Num.post = 0;
-       else if (Num.post + len > FLT_DIG)
-           Num.post = FLT_DIG - len;
+       else if (numstr_pre_len + Num.post > FLT_DIG)
+           Num.post = FLT_DIG - numstr_pre_len;
        snprintf(orgnum, MAXFLOATWIDTH + 1, "%.*f", Num.post, val);
 
        if (*orgnum == '-')
@@ -5351,14 +5360,17 @@ float4_to_char(PG_FUNCTION_ARGS)
            sign = '+';
            numstr = orgnum;
        }
+
        if ((p = strchr(numstr, '.')))
-           len = p - numstr;
+           numstr_pre_len = p - numstr;
        else
-           len = strlen(numstr);
+           numstr_pre_len = strlen(numstr);
 
-       if (Num.pre > len)
-           plen = Num.pre - len;
-       else if (len > Num.pre)
+       /* needs padding? */
+       if (numstr_pre_len < Num.pre)
+           out_pre_spaces = Num.pre - numstr_pre_len;
+       /* overflowed prefix digit format? */
+       else if (numstr_pre_len > Num.pre)
        {
            numstr = (char *) palloc(Num.pre + Num.post + 2);
            fill_str(numstr, '#', Num.pre + Num.post + 1);
@@ -5383,7 +5395,7 @@ float8_to_char(PG_FUNCTION_ARGS)
    FormatNode *format;
    text       *result;
    bool        shouldFree;
-   int         plen = 0,
+   int         out_pre_spaces = 0,
                sign = 0;
    char       *numstr,
               *orgnum,
@@ -5423,7 +5435,7 @@ float8_to_char(PG_FUNCTION_ARGS)
    else
    {
        float8      val = value;
-       int         len;
+       int         numstr_pre_len;
 
        if (IS_MULTI(&Num))
        {
@@ -5433,13 +5445,13 @@ float8_to_char(PG_FUNCTION_ARGS)
            Num.pre += Num.multi;
        }
        orgnum = (char *) palloc(MAXDOUBLEWIDTH + 1);
-       len = snprintf(orgnum, MAXDOUBLEWIDTH + 1, "%.0f", fabs(val));
-       if (Num.pre > len)
-           plen = Num.pre - len;
-       if (len >= DBL_DIG)
+       numstr_pre_len = snprintf(orgnum, MAXDOUBLEWIDTH + 1, "%.0f", fabs(val));
+
+       /* adjust post digits to fit max double digits */
+       if (numstr_pre_len >= DBL_DIG)
            Num.post = 0;
-       else if (Num.post + len > DBL_DIG)
-           Num.post = DBL_DIG - len;
+       else if (numstr_pre_len + Num.post > DBL_DIG)
+           Num.post = DBL_DIG - numstr_pre_len;
        snprintf(orgnum, MAXDOUBLEWIDTH + 1, "%.*f", Num.post, val);
 
        if (*orgnum == '-')
@@ -5452,14 +5464,17 @@ float8_to_char(PG_FUNCTION_ARGS)
            sign = '+';
            numstr = orgnum;
        }
+
        if ((p = strchr(numstr, '.')))
-           len = p - numstr;
+           numstr_pre_len = p - numstr;
        else
-           len = strlen(numstr);
+           numstr_pre_len = strlen(numstr);
 
-       if (Num.pre > len)
-           plen = Num.pre - len;
-       else if (len > Num.pre)
+       /* needs padding? */
+       if (numstr_pre_len < Num.pre)
+           out_pre_spaces = Num.pre - numstr_pre_len;
+       /* overflowed prefix digit format? */
+       else if (numstr_pre_len > Num.pre)
        {
            numstr = (char *) palloc(Num.pre + Num.post + 2);
            fill_str(numstr, '#', Num.pre + Num.post + 1);