Fix compiler warnings in grdppa.c (#122)

* Fix compiler warnings in grdppa.c

* grdppa - Removed gmt_internals.h, added EXTERN_MSC line for gmt_grd_flip_vertical

src/misc/grdppa.c

@@ -15,15 +15,15 @@
  * Contact info: gmt.soest.hawaii.edu
  *--------------------------------------------------------------------*/
 
-/* ********************************************************************* */
-/* Program for automatic extraction of ridge and valley axes from the */
-/* digital elevation data set. The main steps are: */
-/* step 1: data and parameters input by sub._input */
-/* step 2: TarGet ReCognition and CONnection by sub._TGRCON */
-/* step 3: SEGment checK-Out by sub._SEGKO */
-/* step 4: LiNe SMooth and OutPut by sub._LNSMOP
- * 
-/* ********************************************************************* */
+/* *********************************************************************
+ * Program for automatic extraction of ridge and valley axes from the
+ * digital elevation data set. The main steps are:
+ * step 1: data and parameters input by sub._input
+ * step 2: TarGet ReCognition and CONnection by sub._TGRCON
+ * step 3: SEGment checK-Out by sub._SEGKO
+ * step 4: LiNe SMooth and OutPut by sub._LNSMOP
+ *
+ * ********************************************************************* */
 
 #include "gmt_dev.h"
 
@@ -37,6 +37,8 @@
 #define ij(h,i,j) ((i) + ((j)-1)*(h->mx) -1)
 #define ijk(h,i,j,k) ((i) + ((j)-1)*(h->mx) + ((k)-1)*(h->mx)*(h->my) -1)
 
+EXTERN_MSC void gmtlib_grd_flip_vertical (void *gridp, const unsigned n_cols, const unsigned n_rows, const unsigned n_stride, size_t cell_size);
+
 /* Control structure */
 
 struct GRDPPA_CTRL {
@@ -69,11 +71,11 @@ GMT_LOCAL void *New_Ctrl (struct GMT_CTRL *GMT) { /* Allocate and initialize a n
  C->A.ridges = true;
  C->L.n_pts = 3;
  //neigh_x[8] = {0, 1, 1, 1, 0, -1, -1, -1};
- C->neigh_x[0] = 0; C->neigh_x[1] = 1; C->neigh_x[2] = 1; C->neigh_x[3] = 1; 
- C->neigh_x[4] = 0; C->neigh_x[5] = -1; C->neigh_x[6] = -1; C->neigh_x[7] = -1; 
+ C->neigh_x[0] = 0; C->neigh_x[1] = 1; C->neigh_x[2] = 1; C->neigh_x[3] = 1;
+ C->neigh_x[4] = 0; C->neigh_x[5] = -1; C->neigh_x[6] = -1; C->neigh_x[7] = -1;
  //neigh_y[8] = {1, 1, 0, -1, -1, -1, 0, 1};
- C->neigh_y[0] = 1; C->neigh_y[1] = 1; C->neigh_y[2] = 0; C->neigh_y[3] = -1; 
- C->neigh_y[4] = -1; C->neigh_y[5] = -1; C->neigh_y[6] = 0; C->neigh_y[7] = 1; 
+ C->neigh_y[0] = 1; C->neigh_y[1] = 1; C->neigh_y[2] = 0; C->neigh_y[3] = -1;
+ C->neigh_y[4] = -1; C->neigh_y[5] = -1; C->neigh_y[6] = 0; C->neigh_y[7] = 1;
  return (C);
 }
 
@@ -211,7 +213,8 @@ GMT_LOCAL int kst(struct GRDPPA_CTRL *Ctrl, struct GMT_GRID *G, unsigned int i,
  /* jc=4: break the connection, jc=-4: break the route */
  /* jc=8: check number of connections, jc=-8: check number of routes */
  /* ********************************************************************* */
- int ret_val = 0, m, n;
+ int ret_val = 0, m;
+ unsigned int n;
  static float v, w1, w2;
 
  if (jc == 2) {
@@ -423,14 +426,13 @@ int GMT_grdppa (void *V_API, int mode, void *args) {
  bool first = true, mem_G = false;
  unsigned int i, j, k;
  int error = 0;
- 
+
  float z_scale, ww, x, y, v1, v2, x1, y1, x_save, y_save;
  double wesn[4], out[2];
 
- struct GMT_GRID *G = NULL, *W = NULL;
+ struct GMT_GRID *G = NULL;
  struct GMT_RECORD *Out = NULL;
  struct GMT_Z_IO io;
- struct GMT_OPTION *opt = NULL;
  struct GRDPPA_CTRL *Ctrl = NULL;
  struct GMT_CTRL *GMT = NULL, *GMT_cpy = NULL;
  struct GMT_OPTION *options = NULL;
@@ -450,11 +452,11 @@ int GMT_grdppa (void *V_API, int mode, void *args) {
  if (GMT_Parse_Common (API, THIS_MODULE_OPTIONS, options)) Return (API->error);
  Ctrl = New_Ctrl (GMT); /* Allocate and initialize a new control structure */
  if ((error = parse (GMT, Ctrl, &io, options)) != 0) Return (error);
- 
+
  /*---------------------------- This is the grd2xyz main code ----------------------------*/
 
  GMT_Report (API, GMT_MSG_LONG_VERBOSE, "Processing input grid(s)\n");
- 
+
  gmt_M_memcpy (wesn, GMT->common.R.wesn, 4, double); /* Current -R setting, if any */
 
  if (io.binary)