Revert "nanosvg: Sync with upstream cc6c08d"

This reverts commit f697e7879b0c1b37b94b890b3f2a9910e5d822a2.

Part of the update introduced a regression:
https://github.com/memononen/nanosvg/issues/188.

We could include a local revert of the problematic commit but let's just do a
full revert to our previous version, and I'll re-update once the regression
is fixed upstream.

Fixes #43641.

thirdparty/README.md

@@ -435,7 +435,7 @@ Collection of single-file libraries used in Godot components.
 ## nanosvg
 
 - Upstream: https://github.com/memononen/nanosvg
-- Version: git (cc6c08d3a80f1a305021af3d6394cdf1535d02a2, 2020)
+- Version: git (25241c5a8f8451d41ab1b02ab2d865b01600d949, 2019)
 - License: zlib
 
 Files extracted from the upstream source:

thirdparty/nanosvg/nanosvg.h

@@ -225,6 +225,11 @@ static int nsvg__isdigit(char c)
 	return c >= '0' && c <= '9';
 }
 
+static int nsvg__isnum(char c)
+{
+	return strchr("0123456789+-.eE", c) != 0;
+}
+
 static NSVG_INLINE float nsvg__minf(float a, float b) { return a < b ? a : b; }
 static NSVG_INLINE float nsvg__maxf(float a, float b) { return a > b ? a : b; }
 
@@ -731,11 +736,9 @@ static void nsvg__lineTo(NSVGparser* p, float x, float y)
 
 static void nsvg__cubicBezTo(NSVGparser* p, float cpx1, float cpy1, float cpx2, float cpy2, float x, float y)
 {
-	if (p->npts > 0) {
-		nsvg__addPoint(p, cpx1, cpy1);
-		nsvg__addPoint(p, cpx2, cpy2);
-		nsvg__addPoint(p, x, y);
-	}
+	nsvg__addPoint(p, cpx1, cpy1);
+	nsvg__addPoint(p, cpx2, cpy2);
+	nsvg__addPoint(p, x, y);
 }
 
 static NSVGattrib* nsvg__getAttr(NSVGparser* p)
@@ -805,9 +808,7 @@ static float nsvg__convertToPixels(NSVGparser* p, NSVGcoordinate c, float orig,
 static NSVGgradientData* nsvg__findGradientData(NSVGparser* p, const char* id)
 {
 	NSVGgradientData* grad = p->gradients;
-	if (id == NULL || *id == '\0')
-		return NULL;
-	while (grad != NULL) {
+	while (grad) {
 		if (strcmp(grad->id, id) == 0)
 			return grad;
 		grad = grad->next;
@@ -824,26 +825,19 @@ static NSVGgradient* nsvg__createGradient(NSVGparser* p, const char* id, const f
 	NSVGgradient* grad;
 	float ox, oy, sw, sh, sl;
 	int nstops = 0;
-	int refIter;
 
 	data = nsvg__findGradientData(p, id);
 	if (data == NULL) return NULL;
 
 	// TODO: use ref to fill in all unset values too.
 	ref = data;
-	refIter = 0;
 	while (ref != NULL) {
-		NSVGgradientData* nextRef = NULL;
 		if (stops == NULL && ref->stops != NULL) {
 			stops = ref->stops;
 			nstops = ref->nstops;
 			break;
 		}
-		nextRef = nsvg__findGradientData(p, ref->ref);
-		if (nextRef == ref) break; // prevent infite loops on malformed data
-		ref = nextRef;
-		refIter++;
-		if (refIter > 32) break; // prevent infite loops on malformed data
+		ref = nsvg__findGradientData(p, ref->ref);
 	}
 	if (stops == NULL) return NULL;
 
@@ -1046,10 +1040,6 @@ static void nsvg__addPath(NSVGparser* p, char closed)
 	if (closed)
 		nsvg__lineTo(p, p->pts[0], p->pts[1]);
 
-	// Expect 1 + N*3 points (N = number of cubic bezier segments).
-	if ((p->npts % 3) != 1)
-		return;
-
 	path = (NSVGpath*)malloc(sizeof(NSVGpath));
 	if (path == NULL) goto error;
 	memset(path, 0, sizeof(NSVGpath));
@@ -1468,15 +1458,6 @@ static int nsvg__parseUnits(const char* units)
 	return NSVG_UNITS_USER;
 }
 
-static int nsvg__isCoordinate(const char* s)
-{
-	// optional sign
-	if (*s == '-' || *s == '+')
-		s++;
-	// must have at least one digit
-	return nsvg__isdigit(*s);
-}
-
 static NSVGcoordinate nsvg__parseCoordinateRaw(const char* str)
 {
 	NSVGcoordinate coord = {0, NSVG_UNITS_USER};
@@ -1616,32 +1597,25 @@ static int nsvg__parseRotate(float* xform, const char* str)
 static void nsvg__parseTransform(float* xform, const char* str)
 {
 	float t[6];
-	int len;
 	nsvg__xformIdentity(xform);
 	while (*str)
 	{
 		if (strncmp(str, "matrix", 6) == 0)
-			len = nsvg__parseMatrix(t, str);
+			str += nsvg__parseMatrix(t, str);
 		else if (strncmp(str, "translate", 9) == 0)
-			len = nsvg__parseTranslate(t, str);
+			str += nsvg__parseTranslate(t, str);
 		else if (strncmp(str, "scale", 5) == 0)
-			len = nsvg__parseScale(t, str);
+			str += nsvg__parseScale(t, str);
 		else if (strncmp(str, "rotate", 6) == 0)
-			len = nsvg__parseRotate(t, str);
+			str += nsvg__parseRotate(t, str);
 		else if (strncmp(str, "skewX", 5) == 0)
-			len = nsvg__parseSkewX(t, str);
+			str += nsvg__parseSkewX(t, str);
 		else if (strncmp(str, "skewY", 5) == 0)
-			len = nsvg__parseSkewY(t, str);
+			str += nsvg__parseSkewY(t, str);
 		else{
 			++str;
 			continue;
 		}
-		if (len != 0) {
-			str += len;
-		} else {
-			++str;
-			continue;
-		}
 
 		nsvg__xformPremultiply(xform, t);
 	}
@@ -1902,11 +1876,8 @@ static int nsvg__getArgsPerElement(char cmd)
 		case 'a':
 		case 'A':
 			return 7;
-		case 'z':
-		case 'Z':
-			return 0;
 	}
-	return -1;
+	return 0;
 }
 
 static void nsvg__pathMoveTo(NSVGparser* p, float* cpx, float* cpy, float* args, int rel)
@@ -2216,7 +2187,6 @@ static void nsvg__parsePath(NSVGparser* p, const char** attr)
 	float args[10];
 	int nargs;
 	int rargs = 0;
-	char initPoint;
 	float cpx, cpy, cpx2, cpy2;
 	const char* tmp[4];
 	char closedFlag;
@@ -2239,14 +2209,13 @@ static void nsvg__parsePath(NSVGparser* p, const char** attr)
 		nsvg__resetPath(p);
 		cpx = 0; cpy = 0;
 		cpx2 = 0; cpy2 = 0;
-		initPoint = 0;
 		closedFlag = 0;
 		nargs = 0;
 
 		while (*s) {
 			s = nsvg__getNextPathItem(s, item);
 			if (!*item) break;
-			if (cmd != '\0' && nsvg__isCoordinate(item)) {
+			if (nsvg__isnum(item[0])) {
 				if (nargs < 10)
 					args[nargs++] = (float)nsvg__atof(item);
 				if (nargs >= rargs) {
@@ -2259,7 +2228,6 @@ static void nsvg__parsePath(NSVGparser* p, const char** attr)
 							cmd = (cmd == 'm') ? 'l' : 'L';
 							rargs = nsvg__getArgsPerElement(cmd);
 							cpx2 = cpx; cpy2 = cpy;
-							initPoint = 1;
 							break;
 						case 'l':
 						case 'L':
@@ -2309,6 +2277,7 @@ static void nsvg__parsePath(NSVGparser* p, const char** attr)
 				}
 			} else {
 				cmd = item[0];
+				rargs = nsvg__getArgsPerElement(cmd);
 				if (cmd == 'M' || cmd == 'm') {
 					// Commit path.
 					if (p->npts > 0)
@@ -2317,11 +2286,7 @@ static void nsvg__parsePath(NSVGparser* p, const char** attr)
 					nsvg__resetPath(p);
 					closedFlag = 0;
 					nargs = 0;
-				} else if (initPoint == 0) {
-					// Do not allow other commands until initial point has been set (moveTo called once).
-					cmd = '\0';
-				}
-				if (cmd == 'Z' || cmd == 'z') {
+				} else if (cmd == 'Z' || cmd == 'z') {
 					closedFlag = 1;
 					// Commit path.
 					if (p->npts > 0) {
@@ -2337,12 +2302,6 @@ static void nsvg__parsePath(NSVGparser* p, const char** attr)
 					closedFlag = 0;
 					nargs = 0;
 				}
-				rargs = nsvg__getArgsPerElement(cmd);
-				if (rargs == -1) {
-					// Command not recognized
-					cmd = '\0';
-					rargs = 0;
-				}
 			}
 		}
 		// Commit path.