1 #include "adventure.h"
2 
3 #include <stdint.h>
4 #include <stdio.h>
5 #include <stdlib.h>
6 #include <string.h>
7 
8 #include <readline/readline.h>
9 
10 /* the last 32 bits are a version number to be increased on breaking changes.
11  */
12 static const char magic[]
13 	= { 0, 0, 0, 0, 'T', 'E', 'X', 'T', 'A', 'D', 'V', 0, 0, 0, 0 };
14 
15 #define MLEN sizeof(magic)
16 
17 /* Every object is serialized in a buffer with the following format:
18  *
19  *	| offset | location | weight | capacity | health |
20  *
21  * with each field 32 bits long, for a total of 160 bytes.  Each field is a
22  * SIGNED 32 bit integer.  The meaning of the fields is as follows:
23  *
24  * - offset : the current object, that is objs[offset]
25  * - location : the offset of the location, if NULL -1
26  * - weight, capacity, health : the propriety of the object.
27  *
28  * This should make cheating a little bit harder.
29  */
30 
31 int
32 save(void)
33 {
34 	char *line;
35 	FILE *f;
36 	struct object *obj;
37 
38 	line = readline("Save to file: ");
39 	if (!line || !*line) {
40 		printf("Invalid filename\n");
41 
42 		if (line != NULL)
43 			free(line);
44 
45 		return save();
46 	}
47 
48 	/* b = binary mode, for windows compatibility I guess */
49 	if ((f = fopen(line, "wb")) == NULL) {
50 		printf("Cannot write file!\n");
51 		return 0;
52 	}
53 
54 	/* write magic header */
55 	fwrite(magic, 1, MLEN, f);
56 
57 	/* write the objects */
58 	for (obj = objs; obj < obj_end; ++obj) {
59 		int32_t offset, location, weight, capacity, health;
60 
61 		offset = obj - objs;
62 		if (obj->location == NULL)
63 			location = -1;
64 		else
65 			location = obj->location - objs;
66 		weight = obj->weight;
67 		capacity = obj->capacity;
68 		health = obj->health;
69 
70 		printf("saved: %d %d %d %d %d\n", offset, location, weight,
71 			capacity, health);
72 
73 		fwrite(&offset, 4, 1, f);
74 		fwrite(&location, 4, 1, f);
75 		fwrite(&weight, 4, 1, f);
76 		fwrite(&capacity, 4, 1, f);
77 		fwrite(&health, 4, 1, f);
78 	}
79 
80 	fclose(f);
81 	free(line);
82 	return 1;
83 }
84 
85 int
86 load(void)
87 {
88 	char *line, m[MLEN];
89 	FILE *f;
90 	ssize_t r;
91 
92 	line = readline("Load from file: ");
93 	if (!line || !*line) {
94 		printf("Invalid filename\n");
95 
96 		if (line != NULL)
97 			free(line);
98 
99 		return load();
100 	}
101 
102 	if ((f = fopen(line, "rb")) == NULL) {
103 		printf("Cannot open file %s\n", line);
104 		free(line);
105 		return 0;
106 	}
107 
108 	/* read the magic */
109 	fread(m, MLEN, 1, f);
110 	if (memcmp(m, magic, MLEN)) {
111 		printf("Wrong magic in file, cannot load.\n");
112 		goto err;
113 	}
114 
115 	/* read all the objects */
116 	while (1) {
117 		int32_t offset, location, weight, capacity, health;
118 
119 		if ((r = fread(&offset, 1, 4, f)) != 4)
120 			break;
121 		if ((r = fread(&location, 1, 4, f)) != 4)
122 			break;
123 		if ((r = fread(&weight, 1, 4, f)) != 4)
124 			break;
125 		if ((r = fread(&capacity, 1, 4, f)) != 4)
126 			break;
127 		if ((r = fread(&health, 1, 4, f)) != 4)
128 			break;
129 
130 		if (objs + offset >= obj_end)
131 			goto err;
132 
133 		if (location == -1)
134 			objs[offset].location = NULL;
135 		else {
136 			if (objs + location >= obj_end)
137 				goto err;
138 
139 			objs[offset].location = objs + location;
140 		}
141 
142 		objs[offset].weight = weight;
143 		objs[offset].capacity = capacity;
144 		objs[offset].health = health;
145 	}
146 
147 	if (ferror(f)) {
148 		perror(line);
149 		goto err;
150 	}
151 
152 	printf("OK!\n");
153 	fclose(f);
154 	free(line);
155 	return 1;
156 
157 err:
158 	printf("Error in loading file!\n");
159 	fclose(f);
160 	free(line);
161 	return 0;
162 }