Python/dynload_aix.c

   1
   2 /* Support for dynamic loading of extension modules */
   3
   4 #include <ctype.h>      /*  for isdigit()         */
   5 #include <errno.h>      /*  for global errno      */
   6 #include <string.h>     /*  for strerror()        */
   7 #include <stdlib.h>     /*  for malloc(), free()  */
   8 #include <sys/ldr.h>
   9
  10 #include "Python.h"
  11 #include "importdl.h"
  12
  13
  14 #ifdef AIX_GENUINE_CPLUSPLUS
  15 #include "/usr/lpp/xlC/include/load.h"
  16 #define aix_load loadAndInit
  17 #else
  18 #define aix_load load
  19 #endif
  20
  21
  22 extern char *Py_GetProgramName(void);
  23
  24 typedef struct Module {
  25         struct Module *next;
  26         void          *entry;
  27 } Module, *ModulePtr;
  28
  29 const struct filedescr _PyImport_DynLoadFiletab[] = {
  30         {".so", "rb", C_EXTENSION},
  31         {"module.so", "rb", C_EXTENSION},
  32         {0, 0}
  33 };
  34
  35 static int
  36 aix_getoldmodules(void **modlistptr)
  37 {
  38         register ModulePtr       modptr, prevmodptr;
  39         register struct ld_info  *ldiptr;
  40         register char            *ldibuf;
  41         register int             errflag, bufsize = 1024;
  42         register unsigned int    offset;
  43         char *progname = Py_GetProgramName();
  44
  45         /*
  46         -- Get the list of loaded modules into ld_info structures.
  47         */
  48         if ((ldibuf = malloc(bufsize)) == NULL) {
  49                 PyErr_SetString(PyExc_ImportError, strerror(errno));
  50                 return -1;
  51         }
  52         while ((errflag = loadquery(L_GETINFO, ldibuf, bufsize)) == -1
  53                && errno == ENOMEM) {
  54                 free(ldibuf);
  55                 bufsize += 1024;
  56                 if ((ldibuf = malloc(bufsize)) == NULL) {
  57                         PyErr_SetString(PyExc_ImportError, strerror(errno));
  58                         return -1;
  59                 }
  60         }
  61         if (errflag == -1) {
  62                 PyErr_SetString(PyExc_ImportError, strerror(errno));
  63                 return -1;
  64         }
  65         /*
  66         -- Make the modules list from the ld_info structures.
  67         */
  68         ldiptr = (struct ld_info *)ldibuf;
  69         prevmodptr = NULL;
  70         do {
  71                 if (strstr(progname, ldiptr->ldinfo_filename) == NULL &&
  72                     strstr(ldiptr->ldinfo_filename, "python") == NULL) {
  73                         /*
  74                         -- Extract only the modules belonging to the main
  75                         -- executable + those containing "python" as a
  76                         -- substring (like the "python[version]" binary or
  77                         -- "libpython[version].a" in case it's a shared lib).
  78                         */
  79                         offset = (unsigned int)ldiptr->ldinfo_next;
  80                         ldiptr = (struct ld_info *)((unsigned int)
  81                                                     ldiptr + offset);
  82                         continue;
  83                 }
  84                 if ((modptr = (ModulePtr)malloc(sizeof(Module))) == NULL) {
  85                         PyErr_SetString(PyExc_ImportError, strerror(errno));
  86                         while (*modlistptr) {
  87                                 modptr = (ModulePtr)*modlistptr;
  88                                 *modlistptr = (void *)modptr->next;
  89                                 free(modptr);
  90                         }
  91                         return -1;
  92                 }
  93                 modptr->entry = ldiptr->ldinfo_dataorg;
  94                 modptr->next  = NULL;
  95                 if (prevmodptr == NULL)
  96                         *modlistptr = (void *)modptr;
  97                 else
  98                         prevmodptr->next = modptr;
  99                 prevmodptr = modptr;
 100                 offset = (unsigned int)ldiptr->ldinfo_next;
 101                 ldiptr = (struct ld_info *)((unsigned int)ldiptr + offset);
 102         } while (offset);
 103         free(ldibuf);
 104         return 0;
 105 }
 106
 107
 108 static void
 109 aix_loaderror(const char *pathname)
 110 {
 111
 112         char *message[1024], errbuf[1024];
 113         register int i,j;
 114
 115         struct errtab {
 116                 int errNo;
 117                 char *errstr;
 118         } load_errtab[] = {
 119                 {L_ERROR_TOOMANY,       "too many errors, rest skipped."},
 120                 {L_ERROR_NOLIB,         "can't load library:"},
 121                 {L_ERROR_UNDEF,         "can't find symbol in library:"},
 122                 {L_ERROR_RLDBAD,
 123                  "RLD index out of range or bad relocation type:"},
 124                 {L_ERROR_FORMAT,        "not a valid, executable xcoff file:"},
 125                 {L_ERROR_MEMBER,
 126                  "file not an archive or does not contain requested member:"},
 127                 {L_ERROR_TYPE,          "symbol table mismatch:"},
 128                 {L_ERROR_ALIGN,         "text alignment in file is wrong."},
 129                 {L_ERROR_SYSTEM,        "System error:"},
 130                 {L_ERROR_ERRNO,         NULL}
 131         };
 132
 133 #define LOAD_ERRTAB_LEN (sizeof(load_errtab)/sizeof(load_errtab[0]))
 134 #define ERRBUF_APPEND(s) strncat(errbuf, s, sizeof(errbuf)-strlen(errbuf)-1)
 135
 136         PyOS_snprintf(errbuf, sizeof(errbuf), "from module %.200s ", pathname);
 137
 138         if (!loadquery(L_GETMESSAGES, &message[0], sizeof(message))) {
 139                 ERRBUF_APPEND(strerror(errno));
 140                 ERRBUF_APPEND("\n");
 141         }
 142         for(i = 0; message[i] && *message[i]; i++) {
 143                 int nerr = atoi(message[i]);
 144                 for (j=0; j<LOAD_ERRTAB_LEN ; j++) {
 145                     if (nerr == load_errtab[j].errNo && load_errtab[j].errstr)
 146                         ERRBUF_APPEND(load_errtab[j].errstr);
 147                 }
 148                 while (isdigit(*message[i])) message[i]++ ;
 149                 ERRBUF_APPEND(message[i]);
 150                 ERRBUF_APPEND("\n");
 151         }
 152         errbuf[strlen(errbuf)-1] = '\0';        /* trim off last newline */
 153         PyErr_SetString(PyExc_ImportError, errbuf);
 154         return;
 155 }
 156
 157
 158 dl_funcptr _PyImport_GetDynLoadFunc(const char *fqname, const char *shortname,
 159                                     const char *pathname, FILE *fp)
 160 {
 161         dl_funcptr p;
 162
 163         /*
 164         -- Invoke load() with L_NOAUTODEFER leaving the imported symbols
 165         -- of the shared module unresolved. Thus we have to resolve them
 166         -- explicitly with loadbind. The new module is loaded, then we
 167         -- resolve its symbols using the list of already loaded modules
 168         -- (only those that belong to the python executable). Get these
 169         -- with loadquery(L_GETINFO).
 170         */
 171
 172         static void *staticmodlistptr = NULL;
 173
 174         if (!staticmodlistptr)
 175                 if (aix_getoldmodules(&staticmodlistptr) == -1)
 176                         return NULL;
 177         p = (dl_funcptr) aix_load((char *)pathname, L_NOAUTODEFER, 0);
 178         if (p == NULL) {
 179                 aix_loaderror(pathname);
 180                 return NULL;
 181         }
 182
 183         return p;
 184 }