GRASS GIS 8 Programmer's Manual  8.5.0dev(2024)-d6dec75dd4
dspf_header.c
Go to the documentation of this file.
1 #include <string.h>
2 #include <grass/gis.h>
3 #include "viz.h"
4 
5 /*================= DOCUMENT RETURN VALUES! =================*/
6 
8 {
9  int isize, flsize;
10  cmndln_info *linep;
11  FILE *fp;
12  long Where_dataoff;
13 
14  linep = &(headp->linefax);
15  fp = headp->dspfoutfp;
16 
17  isize = sizeof(int);
18  flsize = sizeof(float);
19  /* print the header code on first line of file */
20  if (!fwrite(DSPF_ID, strlen(DSPF_ID), 1, fp))
21  return (-1);
22  /* the dimensions of the data */
23  if (1 != fwrite(&headp->xdim, isize, 1, fp))
24  return (-1);
25  if (1 != fwrite(&headp->ydim, isize, 1, fp))
26  return (-1);
27  if (1 != fwrite(&headp->zdim, isize, 1, fp))
28  return (-1);
29 
30  /* print out code for min and max values */
31  if (1 != fwrite(&headp->min, flsize, 1, fp))
32  return (-1);
33  if (1 != fwrite(&headp->max, flsize, 1, fp))
34  return (-1);
35 
36  /* the litmodel stored for each polygon */
37  if (1 != fwrite(&linep->litmodel, isize, 1, fp))
38  return (-1);
39 
40  /* write the total number of thresholds to be searched for */
41  if (1 != fwrite(&linep->nthres, isize, 1, fp))
42  return (-1);
43  /* write the array of thresholds out */
44  if ((fwrite(linep->tvalue, flsize, linep->nthres, fp)) !=
45  (size_t)linep->nthres) {
46  fprintf(stderr, "ERROR: fwrite in dspf_header.c\n");
47  return (-1);
48  }
49 
50  /* write the offset to the lookup table */
51  /* the first time this number is set to 0 */
52  /*this information will be overwritten after dspf is done */
53  /* G_ftell keeps track of where this information is to be placed */
54  headp->Lookoff = 0;
55  if (1 != fwrite(&headp->Lookoff, sizeof(long), 1, fp))
56  return (-1);
57 
58  /* code to determine the length of the binary file header */
59  /* Dataoff = length of the header */
60  /*Dataoff = strlen (DSPF_ID) + 7*isize + 5*flsize + linep->nthres*flsize; */
61  Where_dataoff = G_ftell(fp);
62  headp->Dataoff = 0;
63  if (1 != fwrite(&headp->Dataoff, sizeof(long), 1, fp))
64  return (-1);
65 
66  /* End of header, now go back and fill in what we can */
67  headp->Dataoff = G_ftell(fp);
68  G_fseek(fp, Where_dataoff, 0);
69  if (1 != fwrite(&headp->Dataoff, sizeof(long), 1, fp))
70  return (-1);
71 
72  G_fseek(fp, headp->Dataoff, 0); /* and return to begin writing data */
73 
74  /* will still have to come back once more to fill in Lookup offset */
75 
76  return (0);
77 }
78 
79 /**************************** dfread_header **********************************/
80 
81 /**************************** dfread_header **********************************/
82 
83 /**************************** dfread_header **********************************/
84 
86 {
87  int isize, flsize;
88  FILE *fp;
89  cmndln_info *linep;
90  char buf[80];
91  int len;
92 
93  fp = headp->dspfinfp;
94 
95  len = strlen(DSPF_ID);
96  G_fseek(fp, 0L, 0); /* rewind file */
97  /*read in header information and store in File_info struct */
98 
99  if (!fread(buf, 1, len, fp))
100  return (-1);
101  buf[len] = 0;
102  if (strncmp(DSPF_ID, buf, len)) {
103  if (!strncmp("dspf003.01", buf, len))
104  return (dfread_header_old(headp, fp));
105 
106  fprintf(stderr, "Error: header mismatch '%s' - '%s'\n", DSPF_ID, buf);
107  return (-1);
108  }
109  linep = &(headp->linefax);
110  isize = sizeof(int);
111  flsize = sizeof(float);
112 
113  if (!fread(&headp->xdim, isize, 1, fp))
114  return (-1);
115  if (!fread(&headp->ydim, isize, 1, fp))
116  return (-1);
117  if (!fread(&headp->zdim, isize, 1, fp))
118  return (-1);
119  if (!fread(&headp->min, flsize, 1, fp))
120  return (-1);
121  if (!fread(&headp->max, flsize, 1, fp))
122  return (-1);
123  if (!fread(&linep->litmodel, isize, 1, fp))
124  return (-1);
125  if (!fread(&linep->nthres, isize, 1, fp))
126  return (-1);
127  if (!fread(linep->tvalue, flsize, linep->nthres, fp))
128  return (-1);
129  if (!fread(&headp->Lookoff, isize, 1, fp))
130  return (-1);
131  if (!fread(&headp->Dataoff, isize, 1, fp))
132  return (-1);
133 
134  print_head_info(headp);
135 
136  return (1);
137 }
138 
139 int dfread_header_old(file_info *headp, FILE *fp)
140 {
141  int isize, flsize;
142  cmndln_info *linep;
143  float tmp;
144 
145  linep = &(headp->linefax);
146  isize = sizeof(int);
147  flsize = sizeof(float);
148 
149  if (!fread(&headp->xdim, isize, 1, fp))
150  return (-1);
151  if (!fread(&headp->ydim, isize, 1, fp))
152  return (-1);
153  if (!fread(&headp->zdim, isize, 1, fp))
154  return (-1);
155  if (!fread(&tmp, flsize, 1, fp))
156  return (-1);
157  if (!fread(&tmp, flsize, 1, fp))
158  return (-1);
159  if (!fread(&tmp, flsize, 1, fp))
160  return (-1);
161  if (!fread(&headp->min, flsize, 1, fp))
162  return (-1);
163  if (!fread(&headp->max, flsize, 1, fp))
164  return (-1);
165  if (!fread(&linep->litmodel, isize, 1, fp))
166  return (-1);
167  if (!fread(&linep->nthres, isize, 1, fp))
168  return (-1);
169  if (!fread(linep->tvalue, flsize, linep->nthres, fp))
170  return (-1);
171  if (!fread(&headp->Lookoff, isize, 1, fp))
172  return (-1);
173  if (!fread(&headp->Dataoff, isize, 1, fp))
174  return (-1);
175 
176  print_head_info(headp);
177 
178  return (1);
179 }
void G_fseek(FILE *, off_t, int)
Change the file position of the stream.
Definition: gis/seek.c:50
off_t G_ftell(FILE *)
Get the current file position of the stream.
Definition: gis/seek.c:29
int dfwrite_header(file_info *headp)
Definition: dspf_header.c:7
int dfread_header_old(file_info *headp, FILE *fp)
Definition: dspf_header.c:139
int dfread_header(file_info *headp)
Definition: dspf_header.c:85
int print_head_info(file_info *head)
Definition: print_info.c:3
float tvalue[MAXTHRESH]
Definition: viz.h:23
int nthres
Definition: viz.h:22
int litmodel
Definition: viz.h:24
Definition: viz.h:27
int zdim
Definition: viz.h:32
long Lookoff
Definition: viz.h:41
int xdim
Definition: viz.h:32
int ydim
Definition: viz.h:32
FILE * dspfoutfp
Definition: viz.h:31
cmndln_info linefax
Definition: viz.h:42
long Dataoff
Definition: viz.h:40
FILE * dspfinfp
Definition: viz.h:31
float min
Definition: viz.h:39
float max
Definition: viz.h:39
#define DSPF_ID
Definition: viz.h:6