Minor cleanup of pj_phi2.c

- tabs -> spaces
- IWYU
- #define -> static const typed
- Combine definition and initialization
- Define one var per statement
- Use the defined symbol rather than embedding bare literals
  -18 -> PJD_ERR_NON_CON_INV_PHI2

Subset of fixes discussed in #971

1 files changed, 25 insertions, 23 deletions

diff --git a/src/pj_phi2.c b/src/pj_phi2.c
index 00b73f70..5f73d510 100644
--- a/src/pj_phi2.c
+++ b/src/pj_phi2.c
@@ -1,28 +1,30 @@
-/* determine latitude angle phi-2 */
+/* Determine latitude angle phi-2. */
+
+#include <math.h>
+
 #include "projects.h"
 
-#define TOL 1.0e-10
-#define N_ITER 15
+static const double TOL = 1.0e-10;
+static const int N_ITER = 15;
+
+double pj_phi2(projCtx ctx, double ts, double e) {
+    double eccnth = .5 * e;
+    double Phi = M_HALFPI - 2. * atan(ts);
+    double con;
+    int i = N_ITER;
+
+    for(;;) {
+        con = e * sin(Phi);
+        double dphi = M_HALFPI - 2. * atan(ts * pow((1. - con) /
+           (1. + con), eccnth)) - Phi;
 
-	double
-pj_phi2(projCtx ctx, double ts, double e) {
-	double eccnth, Phi, con;
-	int i;
+        Phi += dphi;
 
-	eccnth = .5 * e;
-	Phi = M_HALFPI - 2. * atan (ts);
-	i = N_ITER;
-	for(;;) {
-		double dphi;
-		con = e * sin (Phi);
-		dphi = M_HALFPI - 2. * atan (ts * pow((1. - con) /
-		   (1. + con), eccnth)) - Phi;
-		Phi += dphi;
-		if( fabs(dphi) > TOL && --i )
-			continue;
-                break;
-	}
-	if (i <= 0)
-		pj_ctx_set_errno( ctx, -18 );
-	return Phi;
+        if (fabs(dphi) > TOL && --i)
+            continue;
+        break;
+    }
+    if (i <= 0)
+        pj_ctx_set_errno(ctx, PJD_ERR_NON_CON_INV_PHI2);
+    return Phi;
 }