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
|
# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
include <imhdr.h>
include "iki.h"
# IKI_ACCESS -- Determine if the named image exists, and if so, return the
# the index of the IKI kernel to be used to access the image, else return 0 if
# the named image is not found. If multiple images exist with the same name
# (e.g. but with different image types) then ERR is returned. An NEW_IMAGE
# access mode may be specified to associate an extension with an image kernel
# without testing for the existence of an image. If the input image name did
# not specify an extension or what appeared to be an extension was just a .
# delimited field, we will patch up the ROOT and EXTN strings to the real
# values.
int procedure iki_access (image, root, extn, acmode)
char image[ARB] #I image/group name
char root[ARB] #O image/group file name
char extn[ARB] #O image/group file extension
int acmode
bool first_time
int i, k, status, op
pointer sp, osroot, fname, textn, fextn, ip
data first_time /true/
bool fnullfile()
int gstrcpy(), strlen()
errchk fpathname, syserrs
include "iki.com"
begin
call smark (sp)
call salloc (osroot, SZ_PATHNAME, TY_CHAR)
call salloc (fname, SZ_PATHNAME, TY_CHAR)
call salloc (textn, MAX_LENEXTN, TY_CHAR)
call salloc (fextn, MAX_LENEXTN, TY_CHAR)
# The first call makes sure the IKI kernels are loaded into the kernel
# table.
if (first_time) {
call iki_init()
first_time = false
}
call iki_parse (image, root, extn)
if (fnullfile (root)) {
call sfree (sp)
return (1)
}
repeat {
# Convert to absolute pathname to render names like file
# and ./file equivalent. Add a dummy file extension first
# to cause escape sequence encoding of any .DDDD etc. files
# which may be part of the root image name.
op = gstrcpy (root, Memc[fname], SZ_PATHNAME)
call strcpy (".x", Memc[fname+op], SZ_PATHNAME-op+1)
call fpathname (Memc[fname], Memc[osroot], SZ_PATHNAME)
Memc[osroot+strlen(Memc[osroot])-2] = EOS
# Escape any $ in the pathname since we are still in VOS land.
op = 1
for (ip=osroot; Memc[ip] != EOS; ip=ip+1) {
if (Memc[ip] == '$' || Memc[ip] == '[') {
root[op] = '\\'
op = op + 1
}
root[op] = Memc[ip]
op = op + 1
}
root[op] = EOS
# Select an image kernel by calling the access function in each
# loaded kernel until somebody claims the image. If multiple
# kernels claim the image the image specification (name) is
# ambiguous and we don't know which image was intended, an error.
# Note that in the case of a new image, the access function
# tests only the legality of the extn.
k = 0
for (i=1; i <= k_nkernels; i=i+1) {
call strcpy (extn, Memc[textn], MAX_LENEXTN)
call zcall5 (IKI_ACCESS(i), i,root,Memc[textn],acmode,status)
if (status == YES) {
if (k == 0) {
# Stop on the first access if an explicit extension
# was given.
k = i
call strcpy (Memc[textn], Memc[fextn], MAX_LENEXTN)
if (extn[1] != EOS)
break
} else {
# The image name is ambiguous.
call sfree (sp)
return (ERR)
}
}
}
# Valid image using kernel K.
if (k != 0) {
call strcpy (Memc[fextn], extn, MAX_LENEXTN)
call sfree (sp)
return (k)
}
# If the search failed and an extension was given, maybe what
# we thought was an extension was really just part of the root
# filename. Try again with the extn folded into the root.
if (status == NO && extn[1] != EOS) {
call strcpy (image, root, SZ_PATHNAME)
extn[1] = EOS
} else
break
}
call sfree (sp)
return (0)
end
|
