From 4a563fe3005995d76cd987554e060e5fb96063a0 Mon Sep 17 00:00:00 2001
From: Elliott Sales de Andrade <quantum.analyst@gmail.com>
Date: Wed, 24 May 2017 18:45:57 -0400
Subject: [PATCH] Remove confusing macros.

The upper-case macro `VAR` casts the lower-case variable `var` to an
expected type, but that usage obfuscates the variables to the casual
reader. This is especially prevalent in the allocation function in which
`var` is the correct type already, so both `var` and `VAR` are valid
*and* in use.

In any case, for those functions that don't obtain `var` in the correct
type from their parameters, it's much simpler to just case once at the
beginning.
---
 src/pj_gauss.c   | 35 ++++++++++++++++++-----------------
 src/proj_mdist.c | 17 +++++++++--------
 2 files changed, 27 insertions(+), 25 deletions(-)

diff --git a/src/pj_gauss.c b/src/pj_gauss.c
index 70b057f341..41ee8abfac 100644
--- a/src/pj_gauss.c
+++ b/src/pj_gauss.c
@@ -34,7 +34,6 @@ struct GAUSS {
     double e;
     double ratexp;
 };
-#define EN ((struct GAUSS *)en)
 #define DEL_TOL 1e-14
 
 static double srat(double esinp, double exp) {
@@ -48,43 +47,45 @@ void *pj_gauss_ini(double e, double phi0, double *chi, double *rc) {
     if ((en = (struct GAUSS *)malloc(sizeof(struct GAUSS))) == NULL)
         return (NULL);
     es = e * e;
-    EN->e = e;
+    en->e = e;
     sphi = sin(phi0);
     cphi = cos(phi0);  cphi *= cphi;
     *rc = sqrt(1. - es) / (1. - es * sphi * sphi);
-    EN->C = sqrt(1. + es * cphi * cphi / (1. - es));
+    en->C = sqrt(1. + es * cphi * cphi / (1. - es));
     if (en->C == 0.0) {
         free(en);
         return NULL;
     }
-    *chi = asin(sphi / EN->C);
-    EN->ratexp = 0.5 * EN->C * e;
-    EN->K = tan(.5 * *chi + M_FORTPI) / (
-        pow(tan(.5 * phi0 + M_FORTPI), EN->C) *
-        srat(EN->e * sphi, EN->ratexp)  );
+    *chi = asin(sphi / en->C);
+    en->ratexp = 0.5 * en->C * e;
+    en->K = tan(.5 * *chi + M_FORTPI) / (
+        pow(tan(.5 * phi0 + M_FORTPI), en->C) *
+        srat(en->e * sphi, en->ratexp)  );
     return ((void *)en);
 }
 
-LP pj_gauss(projCtx ctx, LP elp, const void *en) {
+LP pj_gauss(projCtx ctx, LP elp, const void *data) {
+    struct GAUSS *en = (struct GAUSS *)data;
     LP slp;
     (void) ctx;
 
-    slp.phi = 2. * atan( EN->K *
-        pow(tan(.5 * elp.phi + M_FORTPI), EN->C) *
-        srat(EN->e * sin(elp.phi), EN->ratexp) ) - M_HALFPI;
-    slp.lam = EN->C * (elp.lam);
+    slp.phi = 2. * atan( en->K *
+        pow(tan(.5 * elp.phi + M_FORTPI), en->C) *
+        srat(en->e * sin(elp.phi), en->ratexp) ) - M_HALFPI;
+    slp.lam = en->C * (elp.lam);
     return(slp);
 }
 
-LP pj_inv_gauss(projCtx ctx, LP slp, const void *en) {
+LP pj_inv_gauss(projCtx ctx, LP slp, const void *data) {
+    struct GAUSS *en = (struct GAUSS *)data;
     LP elp;
     double num;
     int i;
 
-    elp.lam = slp.lam / EN->C;
-    num = pow(tan(.5 * slp.phi + M_FORTPI)/EN->K, 1./EN->C);
+    elp.lam = slp.lam / en->C;
+    num = pow(tan(.5 * slp.phi + M_FORTPI)/en->K, 1./en->C);
     for (i = MAX_ITER; i; --i) {
-        elp.phi = 2. * atan(num * srat(EN->e * sin(slp.phi), -.5 * EN->e))
+        elp.phi = 2. * atan(num * srat(en->e * sin(slp.phi), -.5 * en->e))
             - M_HALFPI;
         if (fabs(elp.phi - slp.phi) < DEL_TOL) break;
             slp.phi = elp.phi;
diff --git a/src/proj_mdist.c b/src/proj_mdist.c
index d7e43443a4..244cf19918 100644
--- a/src/proj_mdist.c
+++ b/src/proj_mdist.c
@@ -38,7 +38,6 @@ struct MDIST {
 	double E;
 	double b[1];
 };
-#define B ((struct MDIST *)b)
 	void *
 proj_mdist_ini(double es) {
 	double numf, numfi, twon1, denf, denfi, ens, T, twon;
@@ -88,28 +87,30 @@ proj_mdist_ini(double es) {
 	return (b);
 }
 	double
-proj_mdist(double phi, double sphi, double cphi, const void *b) {
+proj_mdist(double phi, double sphi, double cphi, const void *data) {
+	struct MDIST *b = (struct MDIST *)data;
 	double sc, sum, sphi2, D;
 	int i;
 
 	sc = sphi * cphi;
 	sphi2 = sphi * sphi;
-	D = phi * B->E - B->es * sc / sqrt(1. - B->es * sphi2);
-	sum = B->b[i = B->nb];
-	while (i) sum = B->b[--i] + sphi2 * sum;
+	D = phi * b->E - b->es * sc / sqrt(1. - b->es * sphi2);
+	sum = b->b[i = b->nb];
+	while (i) sum = b->b[--i] + sphi2 * sum;
 	return(D + sc * sum);
 }
 	double
-proj_inv_mdist(projCtx ctx, double dist, const void *b) {
+proj_inv_mdist(projCtx ctx, double dist, const void *data) {
+	struct MDIST *b = (struct MDIST *)data;
 	double s, t, phi, k;
 	int i;
 
-	k = 1./(1.- B->es);
+	k = 1./(1.- b->es);
 	i = MAX_ITER;
 	phi = dist;
 	while ( i-- ) {
 		s = sin(phi);
-		t = 1. - B->es * s * s;
+		t = 1. - b->es * s * s;
 		phi -= t = (proj_mdist(phi, s, cos(phi), b) - dist) *
 			(t * sqrt(t)) * k;
 		if (fabs(t) < TOL) /* that is no change */