From c29b474280a34175706d7c31df6051d499a90b65 Mon Sep 17 00:00:00 2001
From: Ari Jolma <ari.jolma@gmail.com>
Date: Mon, 27 Sep 2021 14:29:40 +0300
Subject: [PATCH] WCS: Replace CompareNumbers with in-place numeric
 comparisons. (#4550)

---
 autotest/gdrivers/wcs.py         | 40 ++++++++++++++++++++++++++++-
 gdal/frmts/wcs/wcsdataset201.cpp |  9 ++++---
 gdal/frmts/wcs/wcsutils.cpp      | 43 --------------------------------
 gdal/frmts/wcs/wcsutils.h        |  2 --
 4 files changed, 44 insertions(+), 50 deletions(-)

diff --git a/autotest/gdrivers/wcs.py b/autotest/gdrivers/wcs.py
index 9354099bc4d8..518185dc705f 100755
--- a/autotest/gdrivers/wcs.py
+++ b/autotest/gdrivers/wcs.py
@@ -242,6 +242,44 @@ def read_urls():
 wcs_6_ok = True
 
 
+def compare_urls(a, b):
+    """Compare two WCS URLs taking into account that some items are floats
+    """
+    a_list = a.split('&')
+    b_list = b.split('&')
+    n = len(a_list)
+    if n != len(b_list):
+        return False
+    for i in (range(n)):
+        if not re.match('SUBSET=', a_list[i]):
+            if a_list[i] != b_list[i]:
+                print(a_list[i], '!=', b_list[i])
+                return False
+            continue
+        x = a_list[i]
+        y = b_list[i]
+        for c in ('SUBSET=[a-zA-Z]+', '%28', '%29'):
+            x = re.sub(c, '', x)
+            y = re.sub(c, '', y)
+        x_list = x.split(',')
+        y_list = y.split(',')
+        m = len(x_list)
+        if m != len(y_list):
+            return False
+        for j in (range(m)):
+            try:
+                c1 = float(x_list[j])
+                c2 = float(y_list[j])
+            except Exception as e:
+                print(repr(e))
+                return False
+            if c1 == c2:
+                continue
+            if abs((c1-c2)/c1) > 0.001:
+                return False
+    return True
+
+
 class WCSHTTPHandler(BaseHTTPRequestHandler):
 
     def log_request(self, code=',', size=','):
@@ -313,7 +351,7 @@ def do_GET(self):
                 got = re.sub(r'\&test=.*', '', got)
                 _, have = urls[key][test].split('SERVICE=WCS')
                 have += '&server=' + server
-                if got == have:
+                if compare_urls(got, have):
                     ok = 'ok'
                 else:
                     ok = "not ok\ngot:  " + got + "\nhave: " + have
diff --git a/gdal/frmts/wcs/wcsdataset201.cpp b/gdal/frmts/wcs/wcsdataset201.cpp
index 29a4a714f227..80b5828a78ce 100644
--- a/gdal/frmts/wcs/wcsdataset201.cpp
+++ b/gdal/frmts/wcs/wcsdataset201.cpp
@@ -32,6 +32,7 @@
 #include "cpl_string.h"
 #include "cpl_minixml.h"
 #include "cpl_http.h"
+#include "cpl_conv.h"
 #include "gmlutils.h"
 #include "gdal_frmts.h"
 #include "gdal_pam.h"
@@ -182,11 +183,11 @@ CPLString WCSDataset201::GetCoverageRequest(bool scaled,
     std::vector<CPLString> low = Split(CPLGetXMLValue(psService, "Low", ""), ",");
     std::vector<CPLString> high = Split(CPLGetXMLValue(psService, "High", ""), ",");
     CPLString a = CPLString().Printf("%.17g", extent[0]);
-    if (low.size() > 1 && CompareNumbers(low[0], a) > 0) {
+    if (low.size() > 1 && CPLAtof(low[0].c_str()) > extent[0]) {
         a = low[0];
     }
     CPLString b = CPLString().Printf("%.17g", extent[2]);
-    if (high.size() > 1 && CompareNumbers(high[0], b) < 0) {
+    if (high.size() > 1 && CPLAtof(high[0].c_str()) < extent[2]) {
         b = high[0];
     }
     /*
@@ -202,11 +203,11 @@ CPLString WCSDataset201::GetCoverageRequest(bool scaled,
     request += CPLString().Printf("&SUBSET=%s%%28%s,%s%%29", x, a.c_str(), b.c_str());
 
     a = CPLString().Printf("%.17g", extent[1]);
-    if (low.size() > 1 && CompareNumbers(low[1], a) > 0) {
+    if (low.size() > 1 && CPLAtof(low[1].c_str()) > extent[1]) {
         a = low[1];
     }
     b = CPLString().Printf("%.17g", extent[3]);
-    if (high.size() > 1 && CompareNumbers(high[1], b) < 0) {
+    if (high.size() > 1 && CPLAtof(high[1].c_str()) < extent[3]) {
         b = high[1];
     }
     /*
diff --git a/gdal/frmts/wcs/wcsutils.cpp b/gdal/frmts/wcs/wcsutils.cpp
index 1aeb821adbee..6ba4b2a3f424 100644
--- a/gdal/frmts/wcs/wcsutils.cpp
+++ b/gdal/frmts/wcs/wcsutils.cpp
@@ -44,49 +44,6 @@ void Swap(double &a, double &b)
     b = tmp;
 }
 
-int CompareNumbers(const std::string &a, const std::string &b)
-{
-    size_t a_dot = a.find(".");
-    size_t b_dot = b.find(".");
-    std::string a_p = a.substr(0, a_dot);
-    std::string b_p = b.substr(0, b_dot);
-    int d = (int)(a_p.length()) - (int)(b_p.length());
-    if (d < 0) {
-        for (int i = 0; i < -1*d; ++i) {
-            a_p = "0" + a_p;
-        }
-    } else if (d > 0) {
-        for (int i = 0; i < d; ++i) {
-            b_p = "0" + b_p;
-        }
-    }
-    int c = a_p.compare(b_p);
-    if (c < 0) {
-        return -1;
-    } else if (c > 0) {
-        return 1;
-    }
-    a_p = a_dot == std::string::npos ? a : a.substr(a_dot + 1);
-    b_p = b_dot == std::string::npos ? b : b.substr(b_dot + 1);
-    d = (int)(a_p.length()) - (int)(b_p.length());
-    if (d < 0) {
-        for (int i = 0; i < -1*d; ++i) {
-            a_p = a_p + "0";
-        }
-    } else if (d > 0) {
-        for (int i = 0; i < d; ++i) {
-            b_p = b_p + "0";
-        }
-    }
-    c = a_p.compare(b_p);
-    if (c < 0) {
-        return -1;
-    } else if (c > 0) {
-        return 1;
-    }
-    return 0;
-}
-
 CPLString URLEncode(const CPLString &str)
 {
     char *pszEncoded = CPLEscapeString(str, -1, CPLES_URL );
diff --git a/gdal/frmts/wcs/wcsutils.h b/gdal/frmts/wcs/wcsutils.h
index b83c3c0a6756..8e85cd604170 100644
--- a/gdal/frmts/wcs/wcsutils.h
+++ b/gdal/frmts/wcs/wcsutils.h
@@ -37,8 +37,6 @@ namespace WCSUtils {
 
 void Swap(double &a, double &b);
 
-int CompareNumbers(const std::string &a, const std::string &b);
-
 CPLString URLEncode(const CPLString &str);
 
 CPLString URLRemoveKey(const char *url, const CPLString &key);