1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
|
#include <stdlib.h>
#include <string.h>
#include "pm_c_util.h"
#include "mallocvar.h"
#include "shhopt.h"
#include "pgm.h"
struct CmdlineInfo {
/* All the information the user supplied in the command line,
in a form easy for the program to use.
*/
double grayLevel;
unsigned int cols;
unsigned int rows;
gray maxval;
};
static double
grayLevelFromArg(const char * const arg) {
double retval;
if (strlen(arg) < 1)
pm_error("Gray level argument is a null string");
else {
char * endPtr;
retval = strtod(arg, &endPtr);
if (*endPtr != '\0')
pm_error("Gray level argument '%s' is not a floating point number",
arg);
if (retval < 0.0)
pm_error("You can't have a negative gray level (%f)", retval);
if (retval > 1.0)
pm_error("Gray level must be in the range [0.0, 1.0]. "
"You specified %f", retval);
}
return retval;
}
static void
parseCommandLine(int argc, const char ** argv,
struct CmdlineInfo * const cmdlineP) {
/*----------------------------------------------------------------------------
Convert program invocation arguments (argc,argv) into a format the
program can use easily, struct cmdlineInfo. Validate arguments along
the way and exit program with message if invalid.
Note that some string information we return as *cmdlineP is in the storage
argv[] points to.
-----------------------------------------------------------------------------*/
optEntry * option_def;
/* Instructions to OptParseOptions3 on how to parse our options.
*/
optStruct3 opt;
unsigned int maxvalSpec;
unsigned int option_def_index;
MALLOCARRAY_NOFAIL(option_def, 100);
option_def_index = 0; /* incremented by OPTENTRY */
OPTENT3(0, "maxval", OPT_UINT, &cmdlineP->maxval, &maxvalSpec, 0);
opt.opt_table = option_def;
opt.short_allowed = false; /* We have no short (old-fashioned) options */
opt.allowNegNum = false; /* We have no parms that are negative numbers */
pm_optParseOptions3(&argc, (char **)argv, opt, sizeof(opt), 0);
/* Uses and sets argc, argv, and some of *cmdlineP and others. */
if (!maxvalSpec)
cmdlineP->maxval = PGM_MAXMAXVAL;
else {
if (cmdlineP->maxval > PGM_OVERALLMAXVAL)
pm_error("The value you specified for -maxval (%u) is too big. "
"Max allowed is %u", cmdlineP->maxval, PGM_OVERALLMAXVAL);
if (cmdlineP->maxval < 1)
pm_error("You cannot specify 0 for -maxval");
}
if (argc-1 < 3)
pm_error("Need 3 arguments: gray level, width, height.");
else if (argc-1 > 3)
pm_error("Only 3 arguments allowed: gray level, width, height. "
"You specified %d", argc-1);
else {
cmdlineP->grayLevel = grayLevelFromArg(argv[1]);
cmdlineP->cols = pm_parse_width(argv[2]);
cmdlineP->rows = pm_parse_height(argv[3]);
}
free(option_def);
}
int
main(int argc, const char ** const argv) {
struct CmdlineInfo cmdline;
gray * grayrow;
unsigned int col, row;
gray grayLevel;
pm_proginit(&argc, argv);
parseCommandLine(argc, argv, &cmdline);
grayLevel = pgm_unnormalize(cmdline.grayLevel, cmdline.maxval);
pgm_writepgminit(stdout, cmdline.cols, cmdline.rows, cmdline.maxval, 0);
grayrow = pgm_allocrow(cmdline.cols);
/* All rows are identical. Fill once. */
for (col = 0; col < cmdline.cols; ++col)
grayrow[col] = grayLevel;
for (row = 0; row < cmdline.rows; ++row)
pgm_writepgmrow(stdout, grayrow, cmdline.cols, cmdline.maxval, 0);
pgm_freerow(grayrow);
pm_close(stdout);
return 0;
}
|
