1 #include "dlfcn.h"
2 #include "string.h"
3 #include "stdio.h"
4
5 #define INCL_BASE
6 #include <os2.h>
7 #include <float.h>
8 #include <stdlib.h>
9
10 static ULONG retcode;
11 static char fail[300];
12
13 static ULONG dllHandle;
14 static int handle_found;
15 static int handle_loaded;
16 #ifdef PERL_CORE
17
18 #include "EXTERN.h"
19 #include "perl.h"
20
21 #else
22
23 char *os2error(int rc);
24
25 #endif
26
27 #ifdef DLOPEN_INITTERM
_DLL_InitTerm(unsigned long modHandle,unsigned long flag)28 unsigned long _DLL_InitTerm(unsigned long modHandle, unsigned long flag)
29 {
30 switch (flag) {
31 case 0: /* INIT */
32 /* Save handle */
33 dllHandle = modHandle;
34 handle_found = 1;
35 return TRUE;
36
37 case 1: /* TERM */
38 handle_found = 0;
39 dllHandle = (unsigned long)NULLHANDLE;
40 return TRUE;
41 }
42
43 return FALSE;
44 }
45
46 #endif
47
48 HMODULE
find_myself(void)49 find_myself(void)
50 {
51
52 static APIRET APIENTRY (*pDosQueryModFromEIP) (HMODULE * hmod, ULONG * obj, ULONG BufLen, PCHAR Buf,
53 ULONG * Offset, ULONG Address);
54 HMODULE doscalls_h, mod;
55 static int failed;
56 ULONG obj, offset, rc;
57 char buf[260];
58
59 if (failed)
60 return 0;
61 failed = 1;
62 doscalls_h = (HMODULE)dlopen("DOSCALLS",0);
63 if (!doscalls_h)
64 return 0;
65 /* {&doscalls_handle, NULL, 360}, */ /* DosQueryModFromEIP */
66 rc = DosQueryProcAddr(doscalls_h, 360, 0, (PFN*)&pDosQueryModFromEIP);
67 if (rc)
68 return 0;
69 rc = pDosQueryModFromEIP(&mod, &obj, sizeof(buf), buf, &offset, (ULONG)dlopen);
70 if (rc)
71 return 0;
72 failed = 0;
73 handle_found = 1;
74 dllHandle = mod;
75 return mod;
76 }
77
78 void *
dlopen(const char * path,int mode)79 dlopen(const char *path, int mode)
80 {
81 HMODULE handle;
82 char tmp[260];
83 const char *beg, *dot;
84 ULONG rc;
85 unsigned fpflag = _control87(0,0);
86
87 fail[0] = 0;
88 if (!path) { /* Our own handle. */
89 if (handle_found || find_myself()) {
90 char dllname[260];
91
92 if (handle_loaded)
93 return (void*)dllHandle;
94 rc = DosQueryModuleName(dllHandle, sizeof(dllname), dllname);
95 if (rc) {
96 strcpy(fail, "can't find my DLL name by the handle");
97 retcode = rc;
98 return 0;
99 }
100 rc = DosLoadModule(fail, sizeof fail, dllname, &handle);
101 if (rc) {
102 strcpy(fail, "can't load my own DLL");
103 retcode = rc;
104 return 0;
105 }
106 handle_loaded = 1;
107 goto ret;
108 }
109 retcode = ERROR_MOD_NOT_FOUND;
110 strcpy(fail, "can't load from myself: compiled without -DDLOPEN_INITTERM");
111 return 0;
112 }
113 if ((rc = DosLoadModule(fail, sizeof fail, (char*)path, &handle)) == 0)
114 goto ret;
115
116 retcode = rc;
117
118 if (strlen(path) >= sizeof(tmp))
119 return NULL;
120
121 /* Not found. Check for non-FAT name and try truncated name. */
122 /* Don't know if this helps though... */
123 for (beg = dot = path + strlen(path);
124 beg > path && !memCHRs(":/\\", *(beg-1));
125 beg--)
126 if (*beg == '.')
127 dot = beg;
128 if (dot - beg > 8) {
129 int n = beg+8-path;
130
131 memmove(tmp, path, n);
132 memmove(tmp+n, dot, strlen(dot)+1);
133 if (DosLoadModule(fail, sizeof fail, tmp, &handle) == 0)
134 goto ret;
135 }
136 handle = 0;
137
138 ret:
139 _control87(fpflag, MCW_EM); /* Some modules reset FP flags on load */
140 return (void *)handle;
141 }
142
143 #define ERROR_WRONG_PROCTYPE 0xffffffff
144
145 void *
dlsym(void * handle,const char * symbol)146 dlsym(void *handle, const char *symbol)
147 {
148 ULONG rc, type;
149 PFN addr;
150
151 fail[0] = 0;
152 rc = DosQueryProcAddr((HMODULE)handle, 0, symbol, &addr);
153 if (rc == 0) {
154 rc = DosQueryProcType((HMODULE)handle, 0, symbol, &type);
155 if (rc == 0 && type == PT_32BIT)
156 return (void *)addr;
157 rc = ERROR_WRONG_PROCTYPE;
158 }
159 retcode = rc;
160 return NULL;
161 }
162
163 char *
dlerror(void)164 dlerror(void)
165 {
166 static char buf[700];
167 ULONG len;
168 char *err;
169
170 if (retcode == 0)
171 return NULL;
172 if (retcode == ERROR_WRONG_PROCTYPE)
173 err = "Wrong procedure type";
174 else
175 err = os2error(retcode);
176 len = strlen(err);
177 if (len > sizeof(buf) - 1)
178 len = sizeof(buf) - 1;
179 strncpy(buf, err, len+1);
180 if (fail[0] && len + strlen(fail) < sizeof(buf) - 100)
181 sprintf(buf + len, ", possible problematic module: '%s'", fail);
182 retcode = 0;
183 return buf;
184 }
185
186 int
dlclose(void * handle)187 dlclose(void *handle)
188 {
189 ULONG rc;
190
191 if ((rc = DosFreeModule((HMODULE)handle)) == 0) return 0;
192
193 retcode = rc;
194 return 2;
195 }
196