QLocalePrivate: merge removeGroupSeparators into numberToCLocale

This version will parse the string only once and will not do any
memmove. This is more efficient.

Change-Id: I59026ad0fa61cc3f16146bdcd622fc54cbd8a321
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

src/corelib/tools/qlocale.cpp

@@ -3111,6 +3111,11 @@ bool QLocaleData::numberToCLocale(const QChar *str, int len,
             break;
     }
 
+    int group_cnt = 0; // counts number of group chars
+    int decpt_idx = -1;
+    int last_separator_idx = -1;
+    int start_of_digits_idx = -1;
+
     while (idx < l) {
         const QChar in = uc[idx];
 
@@ -3128,20 +3133,60 @@ bool QLocaleData::numberToCLocale(const QChar *str, int len,
             else
                 break;
         }
+        if (group_sep_mode == ParseGroupSeparators) {
+            if (start_of_digits_idx == -1 && out >= '0' && out <= '9') {
+                start_of_digits_idx = idx;
+            } else if (out == ',') {
+                // Don't allow group chars after the decimal point
+                if (decpt_idx != -1)
+                    return false;
+
+                // check distance from the last separator or from the beginning of the digits
+                // ### FIXME: Some locales allow other groupings! See https://en.wikipedia.org/wiki/Thousands_separator
+                if (last_separator_idx != -1 && idx - last_separator_idx != 4)
+                    return false;
+                if (last_separator_idx == -1 && (start_of_digits_idx == -1 || idx - start_of_digits_idx > 3))
+                    return false;
+
+                last_separator_idx = idx;
+                ++group_cnt;
+
+                // don't add the group separator
+                ++idx;
+                continue;
+            } else if (out == '.' || out == 'e' || out == 'E') {
+                // Fail if more than one decimal point
+                if (out == '.' && decpt_idx != -1)
+                    return false;
+                if (decpt_idx == -1)
+                    decpt_idx = idx;
+
+                // check distance from the last separator
+                // ### FIXME: Some locales allow other groupings! See https://en.wikipedia.org/wiki/Thousands_separator
+                if (last_separator_idx != -1 && idx - last_separator_idx != 4)
+                    return false;
+
+                // stop processing separators
+                last_separator_idx = -1;
+            }
+        }
 
         result->append(out);
 
         ++idx;
     }
 
+    if (group_sep_mode == ParseGroupSeparators) {
+        // group separator post-processing
+        // did we end in a separator?
+        if (last_separator_idx + 1 == idx)
+            return false;
+        // were there enough digits since the last separator?
+        if (last_separator_idx != -1 && idx - last_separator_idx != 4)
+            return false;
+    }
+
     result->append('\0');
-
-    // Check separators
-    if (group_sep_mode == ParseGroupSeparators
-            && !removeGroupSeparators(result))
-        return false;
-
-
     return idx == l;
 }
 

src/corelib/tools/qlocale_tools.cpp

@@ -184,80 +184,6 @@ QString &exponentForm(QChar zero, QChar decimal, QChar exponential,
     return digits;
 }
 
-// Removes thousand-group separators in "C" locale.
-bool removeGroupSeparators(QLocaleData::CharBuff *num)
-{
-    int group_cnt = 0; // counts number of group chars
-    int decpt_idx = -1;
-
-    char *data = num->data();
-    int l = qstrlen(data);
-
-    // Find the decimal point and check if there are any group chars
-    int i = 0;
-    for (; i < l; ++i) {
-        char c = data[i];
-
-        if (c == ',') {
-            if (i == 0 || data[i - 1] < '0' || data[i - 1] > '9')
-                return false;
-            if (i == l - 1 || data[i + 1] < '0' || data[i + 1] > '9')
-                return false;
-            ++group_cnt;
-        }
-        else if (c == '.') {
-            // Fail if more than one decimal points
-            if (decpt_idx != -1)
-                return false;
-            decpt_idx = i;
-        } else if (c == 'e' || c == 'E') {
-            // an 'e' or 'E' - if we have not encountered a decimal
-            // point, this is where it "is".
-            if (decpt_idx == -1)
-                decpt_idx = i;
-        }
-    }
-
-    // If no group chars, we're done
-    if (group_cnt == 0)
-        return true;
-
-    // No decimal point means that it "is" at the end of the string
-    if (decpt_idx == -1)
-        decpt_idx = l;
-
-    i = 0;
-    while (i < l && group_cnt > 0) {
-        char c = data[i];
-
-        if (c == ',') {
-            // Don't allow group chars after the decimal point
-            if (i > decpt_idx)
-                return false;
-
-            // Check that it is placed correctly relative to the decpt
-            if ((decpt_idx - i) % 4 != 0)
-                return false;
-
-            // Remove it
-            memmove(data + i, data + i + 1, l - i - 1);
-            data[--l] = '\0';
-
-            --group_cnt;
-            --decpt_idx;
-        } else {
-            // Check that we are not missing a separator
-            if (i < decpt_idx
-                    && (decpt_idx - i) % 4 == 0
-                    && !(i == 0 && (c == '-' || c == '+'))) // check for negative or positive sign at start of string
-                return false;
-            ++i;
-        }
-    }
-
-    return true;
-}
-
 /*-
  * Copyright (c) 1992, 1993
  *        The Regents of the University of California.  All rights reserved.

src/corelib/tools/qlocale_tools_p.h

@@ -104,9 +104,6 @@ inline bool isZero(double d)
     }
 }
 
-// Removes thousand-group separators in "C" locale.
-bool removeGroupSeparators(QLocaleData::CharBuff *num);
-
 Q_CORE_EXPORT char *qdtoa(double d, int mode, int ndigits, int *decpt,
                           int *sign, char **rve, char **digits_str);
 Q_CORE_EXPORT double qstrtod(const char *s00, char const **se, bool *ok);