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-rw-r--r--unix/os/zlocpr.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/unix/os/zlocpr.c b/unix/os/zlocpr.c
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+/* Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+ */
+
+#include <stdio.h>
+#define import_kernel
+#define import_knames
+#define import_spp
+#include <iraf.h>
+
+#ifdef SOLARIS
+#define SUNOS
+#endif
+
+extern unsigned VSHLIB[], VSHEND; /* shared library descriptor */
+
+/* ZLOCPR -- Return the entry point address of a procedure as a magic
+ * integer value. A subsequent call to one of the ZCALL primitives is used
+ * to call the procedure.
+ */
+int
+ZLOCPR (
+ PFI proc, /* procedure for which we desire address */
+ XINT *o_epa /* entry point address */
+)
+{
+ register unsigned *epa = (unsigned *) proc;
+ *o_epa = (XINT) epa;
+
+#ifdef SUNOS
+ /* Return immediately if the shared library is not in use. */
+ if (VSHLIB[0] == 0)
+ return (XOK);
+
+ /* If the shared library is in use and the reference procedure is
+ * a transfer vector, return the address of the actual function.
+ * This is necessary to permit equality comparisons when ZLOCPR
+ * is called to reference the same procedure in both the shared
+ * library image and the client process.
+ */
+ if (epa < VSHLIB || epa >= (unsigned *)&VSHEND)
+ return (XOK);
+
+ /* Disassemble the JMP instruction in the transfer vector to get the
+ * address of the referenced procedure in the shared library. [MACHDEP]
+ */
+#ifdef i386
+ *o_epa = (XINT)((unsigned)epa + *((unsigned *)((char *)epa + 1)) + 5);
+#else
+#ifdef mc68000
+ *o_epa = (XINT)(*((unsigned *)((char *)epa + 2)));
+#else
+#ifdef sparc
+ *o_epa = (XINT)(((*epa & 0x3fffff) << 10) | (*(epa+1) & 0x3ff));
+#endif
+#endif
+#endif
+
+#endif
+
+ return (XOK);
+}