1 /* dlutils.c - handy functions and definitions for dl_*.xs files
2  *
3  * Currently this file is simply #included into dl_*.xs/.c files.
4  * It should really be split into a dlutils.h and dlutils.c
5  *
6  * Modified:
7  * 29th Feburary 2000 - Alan Burlison: Added functionality to close dlopen'd
8  *                      files when the interpreter exits
9  */
10 
11 #define PERL_EUPXS_ALWAYS_EXPORT
12 #ifndef START_MY_CXT /* Some IDEs try compiling this standalone. */
13 #   define PERL_EXT
14 #   include "EXTERN.h"
15 #   include "perl.h"
16 #   include "XSUB.h"
17 #endif
18 
19 #ifndef XS_VERSION
20 #  define XS_VERSION "0"
21 #endif
22 #define MY_CXT_KEY "DynaLoader::_guts" XS_VERSION
23 
24 /* disable version checking since DynaLoader can't be DynaLoaded */
25 #undef dXSBOOTARGSXSAPIVERCHK
26 #define dXSBOOTARGSXSAPIVERCHK dXSBOOTARGSNOVERCHK
27 
28 typedef struct {
29     SV*		x_dl_last_error;	/* pointer to allocated memory for
30                                            last error message */
31 #if defined(PERL_IN_DL_HPUX_XS) || defined(PERL_IN_DL_DLOPEN_XS)
32     int		x_dl_nonlazy;		/* flag for immediate rather than lazy
33                                            linking (spots unresolved symbol) */
34 #endif
35 #ifdef DL_LOADONCEONLY
36     HV *	x_dl_loaded_files;	/* only needed on a few systems */
37 #endif
38 #ifdef DL_CXT_EXTRA
39     my_cxtx_t	x_dl_cxtx;		/* extra platform-specific data */
40 #endif
41 #ifdef DEBUGGING
42     int		x_dl_debug;	/* value copied from $DynaLoader::dl_debug */
43 #endif
44 } my_cxt_t;
45 
46 START_MY_CXT
47 
48 #define dl_last_error	(SvPVX(MY_CXT.x_dl_last_error))
49 #if defined(PERL_IN_DL_HPUX_XS) || defined(PERL_IN_DL_DLOPEN_XS)
50 #define dl_nonlazy	(MY_CXT.x_dl_nonlazy)
51 #endif
52 #ifdef DL_LOADONCEONLY
53 #define dl_loaded_files	(MY_CXT.x_dl_loaded_files)
54 #endif
55 #ifdef DL_CXT_EXTRA
56 #define dl_cxtx		(MY_CXT.x_dl_cxtx)
57 #endif
58 #ifdef DEBUGGING
59 #define dl_debug	(MY_CXT.x_dl_debug)
60 #endif
61 
62 #ifdef DEBUGGING
63 #define DLDEBUG(level,code) \
64     STMT_START {					\
65         dMY_CXT;					\
66         if (dl_debug>=level) { code; }			\
67     } STMT_END
68 #else
69 #define DLDEBUG(level,code)	NOOP
70 #endif
71 
72 #ifdef DL_UNLOAD_ALL_AT_EXIT
73 /* Close all dlopen'd files */
74 static void
dl_unload_all_files(pTHX_ void * unused)75 dl_unload_all_files(pTHX_ void *unused)
76 {
77     CV *sub;
78     PERL_UNUSED_ARG(unused);
79     if ((sub = get_cvs("DynaLoader::dl_unload_file", 0)) != NULL) {
80         AV *dl_librefs = get_av("DynaLoader::dl_librefs", 0);
81         SV *dl_libref;
82         while ((dl_libref = av_pop(dl_librefs)) != &PL_sv_undef) {
83            dSP;
84            ENTER;
85            SAVETMPS;
86            PUSHMARK(SP);
87            XPUSHs(sv_2mortal(dl_libref));
88            PUTBACK;
89            call_sv((SV*)sub, G_DISCARD | G_NODEBUG);
90            FREETMPS;
91            LEAVE;
92         }
93     }
94 }
95 #endif
96 
97 static void
dl_generic_private_init(pTHX)98 dl_generic_private_init(pTHX)	/* called by dl_*.xs dl_private_init() */
99 {
100 #if defined(PERL_IN_DL_HPUX_XS) || defined(PERL_IN_DL_DLOPEN_XS)
101     char *perl_dl_nonlazy;
102     UV uv;
103 #endif
104     MY_CXT_INIT;
105 
106     MY_CXT.x_dl_last_error = newSVpvs("");
107 #ifdef DL_LOADONCEONLY
108     dl_loaded_files = NULL;
109 #endif
110 #ifdef DEBUGGING
111     {
112         SV *sv = get_sv("DynaLoader::dl_debug", 0);
113         dl_debug = sv ? SvIV(sv) : 0;
114     }
115 #endif
116 
117 #if defined(PERL_IN_DL_HPUX_XS) || defined(PERL_IN_DL_DLOPEN_XS)
118     if ( (perl_dl_nonlazy = PerlEnv_getenv("PERL_DL_NONLAZY")) != NULL
119         && grok_atoUV(perl_dl_nonlazy, &uv, NULL)
120         && uv <= INT_MAX
121     ) {
122         dl_nonlazy = (int)uv;
123     } else
124         dl_nonlazy = 0;
125     if (dl_nonlazy)
126         DLDEBUG(1,PerlIO_printf(Perl_debug_log, "DynaLoader bind mode is 'non-lazy'\n"));
127 #endif
128 #ifdef DL_LOADONCEONLY
129     if (!dl_loaded_files)
130         dl_loaded_files = newHV(); /* provide cache for dl_*.xs if needed */
131 #endif
132 #ifdef DL_UNLOAD_ALL_AT_EXIT
133     call_atexit(&dl_unload_all_files, (void*)0);
134 #endif
135 }
136 
137 
138 #ifndef SYMBIAN
139 /* SaveError() takes printf style args and saves the result in dl_last_error */
140 static void
SaveError(pTHX_ const char * pat,...)141 SaveError(pTHX_ const char* pat, ...)
142 {
143     va_list args;
144     SV *msv;
145     const char *message;
146     STRLEN len;
147 
148     /* This code is based on croak/warn, see mess() in util.c */
149 
150     va_start(args, pat);
151     msv = vmess(pat, &args);
152     va_end(args);
153 
154     message = SvPV(msv,len);
155     len++;		/* include terminating null char */
156 
157     {
158         dMY_CXT;
159     /* Copy message into dl_last_error (including terminating null char) */
160         sv_setpvn(MY_CXT.x_dl_last_error, message, len) ;
161         DLDEBUG(2,PerlIO_printf(Perl_debug_log, "DynaLoader: stored error msg '%s'\n",dl_last_error));
162     }
163 }
164 #endif
165 
166