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);