1 #include "include.h"
2 #include "fs.h"
3
4 /*
5 * grab next element from a path, return the pointer to unprocessed portion of
6 * path.
7 */
8 char *
nextelem(char * path,char * elem)9 nextelem(char *path, char *elem)
10 {
11 int i;
12
13 while(*path == '/')
14 path++;
15 if(*path==0 || *path==' ')
16 return 0;
17 for(i=0; *path!='\0' && *path!='/' && *path!=' '; i++){
18 if(i==NAMELEN){
19 print("name component too long\n");
20 return 0;
21 }
22 *elem++ = *path++;
23 }
24 *elem = '\0';
25 return path;
26 }
27
28 int
fswalk(Fs * fs,char * path,File * f)29 fswalk(Fs *fs, char *path, File *f)
30 {
31 char element[NAMELEN];
32
33 *f = fs->root;
34 if(BADPTR(fs->walk))
35 panic("fswalk bad pointer fs->walk");
36
37 f->path = path;
38 while(path = nextelem(path, element)){
39 switch(fs->walk(f, element)){
40 case -1:
41 return -1;
42 case 0:
43 return 0;
44 }
45 }
46 return 1;
47 }
48
49 enum {
50 Bufsize = 8192,
51 };
52
53 /*
54 * boot
55 */
56 int
fsboot(Fs * fs,char * path,Boot * b)57 fsboot(Fs *fs, char *path, Boot *b)
58 {
59 File file;
60 long n;
61 static char *buf;
62
63 if (buf == nil)
64 buf = malloc(Bufsize + 1);
65 switch(fswalk(fs, path, &file)){
66 case -1:
67 print("error walking to %s\n", path);
68 return -1;
69 case 0:
70 print("%s not found\n", path);
71 return -1;
72 case 1:
73 print("found %s\n", path);
74 break;
75 }
76
77 while((n = fsread(&file, buf, Bufsize)) > 0) {
78 if(bootpass(b, buf, n) != MORE)
79 break;
80 }
81
82 bootpass(b, nil, 0); /* tries boot */
83 return -1;
84 }
85
86 int
fsread(File * file,void * a,long n)87 fsread(File *file, void *a, long n)
88 {
89 if(BADPTR(file->fs))
90 panic("bad pointer file->fs in fsread");
91 if(BADPTR(file->fs->read))
92 panic("bad pointer file->fs->read in fsread");
93 return file->fs->read(file, a, n);
94 }
95