Merge commit '98acd3f494b28ddd8c345a2bb9311e41e2d56ddd' as 'tcl8.6'

1 files changed, 630 insertions, 0 deletions

diff --git a/tcl8.6/unix/tclLoadAix.c b/tcl8.6/unix/tclLoadAix.c
new file mode 100644
index 0000000..88e6b50
--- /dev/null
+++ b/tcl8.6/unix/tclLoadAix.c
@@ -0,0 +1,630 @@
+/*
+ * tclLoadAix.c --
+ *
+ *	This file implements the dlopen and dlsym APIs under the AIX operating
+ *	system, to enable the Tcl "load" command to work. This code was
+ *	provided by Jens-Uwe Mager.
+ *
+ *	This file is subject to the following copyright notice, which is
+ *	different from the notice used elsewhere in Tcl. The file has been
+ *	modified to incorporate the file dlfcn.h in-line.
+ *
+ *	Copyright (c) 1992,1993,1995,1996, Jens-Uwe Mager, Helios Software GmbH
+ *	Not derived from licensed software.
+ *
+ *	Permission is granted to freely use, copy, modify, and redistribute
+ *	this software, provided that the author is not construed to be liable
+ *	for any results of using the software, alterations are clearly marked
+ *	as such, and this notice is not modified.
+ *
+ * Note: this file has been altered from the original in a few ways in order
+ * to work properly with Tcl.
+ */
+
+/*
+ * @(#)dlfcn.c	1.7 revision of 95/08/14  19:08:38
+ * This is an unpublished work copyright (c) 1992 HELIOS Software GmbH
+ * 30159 Hannover, Germany
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/ldr.h>
+#include <a.out.h>
+#include <ldfcn.h>
+#include "../compat/dlfcn.h"
+
+/*
+ * We simulate dlopen() et al. through a call to load. Because AIX has no call
+ * to find an exported symbol we read the loader section of the loaded module
+ * and build a list of exported symbols and their virtual address.
+ */
+
+typedef struct {
+    char *name;			/* The symbols's name. */
+    void *addr;			/* Its relocated virtual address. */
+} Export, *ExportPtr;
+
+/*
+ * xlC uses the following structure to list its constructors and destructors.
+ * This is gleaned from the output of munch.
+ */
+
+typedef struct {
+    void (*init)(void);		/* call static constructors */
+    void (*term)(void);		/* call static destructors */
+} Cdtor, *CdtorPtr;
+
+/*
+ * The void * handle returned from dlopen is actually a ModulePtr.
+ */
+
+typedef struct Module {
+    struct Module *next;
+    char *name;			/* module name for refcounting */
+    int refCnt;			/* the number of references */
+    void *entry;		/* entry point from load */
+    struct dl_info *info;	/* optional init/terminate functions */
+    CdtorPtr cdtors;		/* optional C++ constructors */
+    int nExports;		/* the number of exports found */
+    ExportPtr exports;		/* the array of exports */
+} Module, *ModulePtr;
+
+/*
+ * We keep a list of all loaded modules to be able to call the fini handlers
+ * and destructors at atexit() time.
+ */
+
+static ModulePtr modList;
+
+/*
+ * The last error from one of the dl* routines is kept in static variables
+ * here. Each error is returned only once to the caller.
+ */
+
+static char errbuf[BUFSIZ];
+static int errvalid;
+
+static void caterr(char *);
+static int readExports(ModulePtr);
+static void terminate(void);
+static void *findMain(void);
+
+void *
+dlopen(
+    const char *path,
+    int mode)
+{
+    register ModulePtr mp;
+    static void *mainModule;
+
+    /*
+     * Upon the first call register a terminate handler that will close all
+     * libraries. Also get a reference to the main module for use with
+     * loadbind.
+     */
+
+    if (!mainModule) {
+	mainModule = findMain();
+	if (mainModule == NULL) {
+	    return NULL;
+	}
+	atexit(terminate);
+    }
+
+    /*
+     * Scan the list of modules if we have the module already loaded.
+     */
+
+    for (mp = modList; mp; mp = mp->next) {
+	if (strcmp(mp->name, path) == 0) {
+	    mp->refCnt++;
+	    return (void *) mp;
+	}
+    }
+
+    mp = (ModulePtr) calloc(1, sizeof(*mp));
+    if (mp == NULL) {
+	errvalid++;
+	strcpy(errbuf, "calloc: ");
+	strcat(errbuf, strerror(errno));
+	return NULL;
+    }
+
+    mp->name = malloc((unsigned) (strlen(path) + 1));
+    strcpy(mp->name, path);
+
+    /*
+     * load should be declared load(const char *...). Thus we cast the path to
+     * a normal char *. Ugly.
+     */
+
+    mp->entry = (void *) load((char *)path, L_NOAUTODEFER, NULL);
+    if (mp->entry == NULL) {
+	free(mp->name);
+	free(mp);
+	errvalid++;
+	strcpy(errbuf, "dlopen: ");
+	strcat(errbuf, path);
+	strcat(errbuf, ": ");
+
+	/*
+	 * If AIX says the file is not executable, the error can be further
+	 * described by querying the loader about the last error.
+	 */
+
+	if (errno == ENOEXEC) {
+	    char *tmp[BUFSIZ/sizeof(char *)], **p;
+
+	    if (loadquery(L_GETMESSAGES, tmp, sizeof(tmp)) == -1) {
+		strcpy(errbuf, strerror(errno));
+	    } else {
+		for (p=tmp ; *p ; p++) {
+		    caterr(*p);
+		}
+	    }
+	} else {
+	    strcat(errbuf, strerror(errno));
+	}
+	return NULL;
+    }
+
+    mp->refCnt = 1;
+    mp->next = modList;
+    modList = mp;
+
+    if (loadbind(0, mainModule, mp->entry) == -1) {
+    loadbindFailure:
+	dlclose(mp);
+	errvalid++;
+	strcpy(errbuf, "loadbind: ");
+	strcat(errbuf, strerror(errno));
+	return NULL;
+    }
+
+    /*
+     * If the user wants global binding, loadbind against all other loaded
+     * modules.
+     */
+
+    if (mode & RTLD_GLOBAL) {
+	register ModulePtr mp1;
+
+	for (mp1 = mp->next; mp1; mp1 = mp1->next) {
+	    if (loadbind(0, mp1->entry, mp->entry) == -1) {
+		goto loadbindFailure;
+	    }
+	}
+    }
+
+    if (readExports(mp) == -1) {
+	dlclose(mp);
+	return NULL;
+    }
+
+    /*
+     * If there is a dl_info structure, call the init function.
+     */
+
+    if (mp->info = (struct dl_info *)dlsym(mp, "dl_info")) {
+	if (mp->info->init) {
+	    mp->info->init();
+	}
+    } else {
+	errvalid = 0;
+    }
+
+    /*
+     * If the shared object was compiled using xlC we will need to call static
+     * constructors (and later on dlclose destructors).
+     */
+
+    if (mp->cdtors = (CdtorPtr) dlsym(mp, "__cdtors")) {
+	while (mp->cdtors->init) {
+	    mp->cdtors->init();
+	    mp->cdtors++;
+	}
+    } else {
+	errvalid = 0;
+    }
+
+    return (void *) mp;
+}
+
+/*
+ * Attempt to decipher an AIX loader error message and append it to our static
+ * error message buffer.
+ */
+
+static void
+caterr(
+    char *s)
+{
+    register char *p = s;
+
+    while (*p >= '0' && *p <= '9') {
+	p++;
+    }
+    switch (atoi(s)) {		/* INTL: "C", UTF safe. */
+    case L_ERROR_TOOMANY:
+	strcat(errbuf, "to many errors");
+	break;
+    case L_ERROR_NOLIB:
+	strcat(errbuf, "can't load library");
+	strcat(errbuf, p);
+	break;
+    case L_ERROR_UNDEF:
+	strcat(errbuf, "can't find symbol");
+	strcat(errbuf, p);
+	break;
+    case L_ERROR_RLDBAD:
+	strcat(errbuf, "bad RLD");
+	strcat(errbuf, p);
+	break;
+    case L_ERROR_FORMAT:
+	strcat(errbuf, "bad exec format in");
+	strcat(errbuf, p);
+	break;
+    case L_ERROR_ERRNO:
+	strcat(errbuf, strerror(atoi(++p)));	/* INTL: "C", UTF safe. */
+	break;
+    default:
+	strcat(errbuf, s);
+	break;
+    }
+}
+
+void *
+dlsym(
+    void *handle,
+    const char *symbol)
+{
+    register ModulePtr mp = (ModulePtr)handle;
+    register ExportPtr ep;
+    register int i;
+
+    /*
+     * Could speed up the search, but I assume that one assigns the result to
+     * function pointers anyways.
+     */
+
+    for (ep = mp->exports, i = mp->nExports; i; i--, ep++) {
+	if (strcmp(ep->name, symbol) == 0) {
+	    return ep->addr;
+	}
+    }
+
+    errvalid++;
+    strcpy(errbuf, "dlsym: undefined symbol ");
+    strcat(errbuf, symbol);
+    return NULL;
+}
+
+char *
+dlerror(void)
+{
+    if (errvalid) {
+	errvalid = 0;
+	return errbuf;
+    }
+    return NULL;
+}
+
+int
+dlclose(
+    void *handle)
+{
+    register ModulePtr mp = (ModulePtr)handle;
+    int result;
+    register ModulePtr mp1;
+
+    if (--mp->refCnt > 0) {
+	return 0;
+    }
+
+    if (mp->info && mp->info->fini) {
+	mp->info->fini();
+    }
+
+    if (mp->cdtors) {
+	while (mp->cdtors->term) {
+	    mp->cdtors->term();
+	    mp->cdtors++;
+	}
+    }
+
+    result = unload(mp->entry);
+    if (result == -1) {
+	errvalid++;
+	strcpy(errbuf, strerror(errno));
+    }
+
+    if (mp->exports) {
+	register ExportPtr ep;
+	register int i;
+	for (ep = mp->exports, i = mp->nExports; i; i--, ep++) {
+	    if (ep->name) {
+		free(ep->name);
+	    }
+	}
+	free(mp->exports);
+    }
+
+    if (mp == modList) {
+	modList = mp->next;
+    } else {
+	for (mp1 = modList; mp1; mp1 = mp1->next) {
+	    if (mp1->next == mp) {
+		mp1->next = mp->next;
+		break;
+	    }
+	}
+    }
+
+    free(mp->name);
+    free(mp);
+    return result;
+}
+
+static void
+terminate(void)
+{
+    while (modList) {
+	dlclose(modList);
+    }
+}
+
+/*
+ * Build the export table from the XCOFF .loader section.
+ */
+
+static int
+readExports(
+    ModulePtr mp)
+{
+    LDFILE *ldp = NULL;
+    SCNHDR sh, shdata;
+    LDHDR *lhp;
+    char *ldbuf;
+    LDSYM *ls;
+    int i;
+    ExportPtr ep;
+    const char *errMsg;
+
+#define Error(msg) do{errMsg=(msg);goto error;}while(0)
+#define SysErr() Error(strerror(errno))
+
+    ldp = ldopen(mp->name, ldp);
+    if (ldp == NULL) {
+	struct ld_info *lp;
+	char *buf;
+	int size = 0;
+
+	if (errno != ENOENT) {
+	    SysErr();
+	}
+
+	/*
+	 * The module might be loaded due to the LIBPATH environment variable.
+	 * Search for the loaded module using L_GETINFO.
+	 */
+
+	while (1) {
+	    size += 4 * 1024;
+	    buf = malloc(size);
+	    if (buf == NULL) {
+		SysErr();
+	    }
+
+	    i = loadquery(L_GETINFO, buf, size);
+
+	    if (i != -1) {
+		break;
+	    }
+	    free(buf);
+	    if (errno != ENOMEM) {
+		SysErr();
+	    }
+	}
+
+	/*
+	 * Traverse the list of loaded modules. The entry point returned by
+	 * load() does actually point to the data segment origin.
+	 */
+
+	lp = (struct ld_info *) buf;
+	while (lp) {
+	    if (lp->ldinfo_dataorg == mp->entry) {
+		ldp = ldopen(lp->ldinfo_filename, ldp);
+		break;
+	    }
+	    if (lp->ldinfo_next == 0) {
+		lp = NULL;
+	    } else {
+		lp = (struct ld_info *)((char *)lp + lp->ldinfo_next);
+	    }
+	}
+
+	free(buf);
+
+	if (!ldp) {
+	    SysErr();
+	}
+    }
+
+    if (TYPE(ldp) != U802TOCMAGIC) {
+	Error("bad magic");
+    }
+
+    /*
+     * Get the padding for the data section. This is needed for AIX 4.1
+     * compilers. This is used when building the final function pointer to the
+     * exported symbol.
+     */
+
+    if (ldnshread(ldp, _DATA, &shdata) != SUCCESS) {
+	Error("cannot read data section header");
+    }
+
+    if (ldnshread(ldp, _LOADER, &sh) != SUCCESS) {
+	Error("cannot read loader section header");
+    }
+
+    /*
+     * We read the complete loader section in one chunk, this makes finding
+     * long symbol names residing in the string table easier.
+     */
+
+    ldbuf = (char *) malloc(sh.s_size);
+    if (ldbuf == NULL) {
+	SysErr();
+    }
+
+    if (FSEEK(ldp, sh.s_scnptr, BEGINNING) != OKFSEEK) {
+	free(ldbuf);
+	Error("cannot seek to loader section");
+    }
+
+    if (FREAD(ldbuf, sh.s_size, 1, ldp) != 1) {
+	free(ldbuf);
+	Error("cannot read loader section");
+    }
+
+    lhp = (LDHDR *) ldbuf;
+    ls = (LDSYM *)(ldbuf + LDHDRSZ);
+
+    /*
+     * Count the number of exports to include in our export table.
+     */
+
+    for (i = lhp->l_nsyms; i; i--, ls++) {
+	if (!LDR_EXPORT(*ls)) {
+	    continue;
+	}
+	mp->nExports++;
+    }
+
+    mp->exports = (ExportPtr) calloc(mp->nExports, sizeof(*mp->exports));
+    if (mp->exports == NULL) {
+	free(ldbuf);
+	SysErr();
+    }
+
+    /*
+     * Fill in the export table. All entries are relative to the entry point
+     * we got from load.
+     */
+
+    ep = mp->exports;
+    ls = (LDSYM *)(ldbuf + LDHDRSZ);
+    for (i=lhp->l_nsyms ; i!=0 ; i--,ls++) {
+	char *symname;
+	char tmpsym[SYMNMLEN+1];
+
+	if (!LDR_EXPORT(*ls)) {
+	    continue;
+	}
+
+	if (ls->l_zeroes == 0) {
+	    symname = ls->l_offset + lhp->l_stoff + ldbuf;
+	} else {
+	    /*
+	     * The l_name member is not zero terminated, we must copy the
+	     * first SYMNMLEN chars and make sure we have a zero byte at the
+	     * end.
+	     */
+
+	    strncpy(tmpsym, ls->l_name, SYMNMLEN);
+	    tmpsym[SYMNMLEN] = '\0';
+	    symname = tmpsym;
+	}
+	ep->name = malloc((unsigned) (strlen(symname) + 1));
+	strcpy(ep->name, symname);
+	ep->addr = (void *)((unsigned long)
+		mp->entry + ls->l_value - shdata.s_vaddr);
+	ep++;
+    }
+    free(ldbuf);
+    while (ldclose(ldp) == FAILURE) {
+	/* Empty body */
+    }
+    return 0;
+
+    /*
+     * This is a factoring out of the error-handling code to make the rest of
+     * the function much simpler to read.
+     */
+
+  error:
+    errvalid++;
+    strcpy(errbuf, "readExports: ");
+    strcat(errbuf, errMsg);
+
+    if (ldp != NULL) {
+	while (ldclose(ldp) == FAILURE) {
+	    /* Empty body */
+	}
+    }
+    return -1;
+}
+
+/*
+ * Find the main modules entry point. This is used as export pointer for
+ * loadbind() to be able to resolve references to the main part.
+ */
+
+static void *
+findMain(void)
+{
+    struct ld_info *lp;
+    char *buf;
+    int size = 4*1024;
+    int i;
+    void *ret;
+
+    buf = malloc(size);
+    if (buf == NULL) {
+	goto error;
+    }
+
+    while ((i = loadquery(L_GETINFO, buf, size)) == -1 && errno == ENOMEM) {
+	free(buf);
+	size += 4*1024;
+	buf = malloc(size);
+	if (buf == NULL) {
+	    goto error;
+	}
+    }
+
+    if (i == -1) {
+	free(buf);
+	goto error;
+    }
+
+    /*
+     * The first entry is the main module. The entry point returned by load()
+     * does actually point to the data segment origin.
+     */
+
+    lp = (struct ld_info *) buf;
+    ret = lp->ldinfo_dataorg;
+    free(buf);
+    return ret;
+
+  error:
+    errvalid++;
+    strcpy(errbuf, "findMain: ");
+    strcat(errbuf, strerror(errno));
+    return NULL;
+}
+
+/*
+ * Local Variables:
+ * mode: c
+ * c-basic-offset: 4
+ * fill-column: 78
+ * End:
+ */