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author | dkf <donal.k.fellows@manchester.ac.uk> | 2005-07-19 13:37:18 (GMT) |
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committer | dkf <donal.k.fellows@manchester.ac.uk> | 2005-07-19 13:37:18 (GMT) |
commit | eef397f7b3a6573ff3515eb563eb75feb4ff0fa6 (patch) | |
tree | ea419974455924f2dd9c3f1d47c703d8976fa51e /unix/tclLoadAout.c | |
parent | 52a2f42701d8f0deeacf5b47bed3883355781439 (diff) | |
download | tcl-eef397f7b3a6573ff3515eb563eb75feb4ff0fa6.zip tcl-eef397f7b3a6573ff3515eb563eb75feb4ff0fa6.tar.gz tcl-eef397f7b3a6573ff3515eb563eb75feb4ff0fa6.tar.bz2 |
Systematizing the formatting
Also simplified the AIX loader so that it's failure-mode code wasn't scattered
all over quite so much.
Diffstat (limited to 'unix/tclLoadAout.c')
-rw-r--r-- | unix/tclLoadAout.c | 459 |
1 files changed, 249 insertions, 210 deletions
diff --git a/unix/tclLoadAout.c b/unix/tclLoadAout.c index d4ef456..7557a94 100644 --- a/unix/tclLoadAout.c +++ b/unix/tclLoadAout.c @@ -1,20 +1,20 @@ -/* +/* * tclLoadAout.c -- * - * This procedure provides a version of the TclLoadFile that - * provides pseudo-static linking using version-7 compatible - * a.out files described in either sys/exec.h or sys/a.out.h. + * This procedure provides a version of the TclLoadFile that provides + * pseudo-static linking using version-7 compatible a.out files described + * in either sys/exec.h or sys/a.out.h. * * Copyright (c) 1995, by General Electric Company. All rights reserved. * - * See the file "license.terms" for information on usage and redistribution - * of this file, and for a DISCLAIMER OF ALL WARRANTIES. + * See the file "license.terms" for information on usage and redistribution of + * this file, and for a DISCLAIMER OF ALL WARRANTIES. * - * This work was supported in part by the ARPA Manufacturing Automation - * and Design Engineering (MADE) Initiative through ARPA contract + * This work was supported in part by the ARPA Manufacturing Automation and + * Design Engineering (MADE) Initiative through ARPA contract * F33615-94-C-4400. * - * RCS: @(#) $Id: tclLoadAout.c,v 1.14 2002/10/10 12:25:53 vincentdarley Exp $ + * RCS: @(#) $Id: tclLoadAout.c,v 1.15 2005/07/19 13:37:18 dkf Exp $ */ #include "tclInt.h" @@ -29,8 +29,7 @@ #endif /* - * Some systems describe the a.out header in sys/exec.h, and some in - * a.out.h. + * Some systems describe the a.out header in sys/exec.h, and some in a.out.h. */ #ifdef USE_SYS_EXEC_H @@ -49,91 +48,90 @@ */ #ifndef TCL_LOADSHIM -#define TCL_LOADSHIM 0x4000L +#define TCL_LOADSHIM 0x4000L #endif /* - * TCL_LOADALIGN must be a power of 2, and is the alignment to which - * to force the origin of load modules + * TCL_LOADALIGN must be a power of 2, and is the alignment to which to force + * the origin of load modules */ #ifndef TCL_LOADALIGN -#define TCL_LOADALIGN 0x4000L +#define TCL_LOADALIGN 0x4000L #endif /* - * TCL_LOADMAX is the maximum size of a load module, and is used as - * a sanity check when loading + * TCL_LOADMAX is the maximum size of a load module, and is used as a sanity + * check when loading */ #ifndef TCL_LOADMAX -#define TCL_LOADMAX 2000000L +#define TCL_LOADMAX 2000000L #endif /* * Kernel calls that appear to be missing from the system .h files: */ -extern char * brk _ANSI_ARGS_((char *)); -extern char * sbrk _ANSI_ARGS_((size_t)); +extern char * brk _ANSI_ARGS_((char *)); +extern char * sbrk _ANSI_ARGS_((size_t)); /* - * The static variable SymbolTableFile contains the file name where the - * result of the last link was stored. The file is kept because doing so - * allows one load module to use the symbols defined in another. + * The static variable SymbolTableFile contains the file name where the result + * of the last link was stored. The file is kept because doing so allows one + * load module to use the symbols defined in another. */ -static char * SymbolTableFile = NULL; +static char *SymbolTableFile = NULL; /* * Type of the dictionary function that begins each load module. */ -typedef Tcl_PackageInitProc * (* DictFn) _ANSI_ARGS_ ((CONST char * symbol)); +typedef Tcl_PackageInitProc * (* DictFn) _ANSI_ARGS_((CONST char * symbol)); /* * Prototypes for procedures referenced only in this file: */ -static int FindLibraries _ANSI_ARGS_((Tcl_Interp * interp, Tcl_Obj * pathPtr, - Tcl_DString * buf)); -static void UnlinkSymbolTable _ANSI_ARGS_((void)); +static int FindLibraries _ANSI_ARGS_((Tcl_Interp *interp, + Tcl_Obj *pathPtr, Tcl_DString *buf)); +static void UnlinkSymbolTable _ANSI_ARGS_((void)); /* *---------------------------------------------------------------------- * * TclpDlopen -- * - * Dynamically loads a binary code file into memory and returns - * a handle to the new code. + * Dynamically loads a binary code file into memory and returns a handle + * to the new code. * * Results: - * A standard Tcl completion code. If an error occurs, an error - * message is left in the interp's result. + * A standard Tcl completion code. If an error occurs, an error message + * is left in the interp's result. * * Side effects: * New code suddenly appears in memory. * - * * Bugs: - * This function does not attempt to handle the case where the - * BSS segment is not executable. It will therefore fail on - * Encore Multimax, Pyramid 90x, and similar machines. The - * reason is that the mprotect() kernel call, which would - * otherwise be employed to mark the newly-loaded text segment - * executable, results in a system crash on BSD/386. - * - * In an effort to make it fast, this function eschews the - * technique of linking the load module once, reading its header - * to determine its size, allocating memory for it, and linking - * it again. Instead, it `shims out' memory allocation by - * placing the module TCL_LOADSHIM bytes beyond the break, - * and assuming that any malloc() calls required to run the - * linker will not advance the break beyond that point. If - * the break is advanced beyonnd that point, the load will - * fail with an `inconsistent memory allocation' error. - * It perhaps ought to retry the link, but the failure has - * not been observed in two years of daily use of this function. + * This function does not attempt to handle the case where the BSS + * segment is not executable. It will therefore fail on Encore Multimax, + * Pyramid 90x, and similar machines. The reason is that the mprotect() + * kernel call, which would otherwise be employed to mark the + * newly-loaded text segment executable, results in a system crash on + * BSD/386. + * + * In an effort to make it fast, this function eschews the technique of + * linking the load module once, reading its header to determine its + * size, allocating memory for it, and linking it again. Instead, it + * `shims out' memory allocation by placing the module TCL_LOADSHIM bytes + * beyond the break, and assuming that any malloc() calls required to run + * the linker will not advance the break beyond that point. If the break + * is advanced beyonnd that point, the load will fail with an + * `inconsistent memory allocation' error. It perhaps ought to retry the + * link, but the failure has not been observed in two years of daily use + * of this function. + * *---------------------------------------------------------------------- */ @@ -143,17 +141,17 @@ TclpDlopen(interp, pathPtr, loadHandle, unloadProcPtr) Tcl_Obj *pathPtr; /* Name of the file containing the desired * code (UTF-8). */ Tcl_LoadHandle *loadHandle; /* Filled with token for dynamically loaded - * file which will be passed back to + * file which will be passed back to * (*unloadProcPtr)() to unload the file. */ - Tcl_FSUnloadFileProc **unloadProcPtr; + Tcl_FSUnloadFileProc **unloadProcPtr; /* Filled with address of Tcl_FSUnloadFileProc - * function which should be used for - * this file. */ + * function which should be used for this + * file. */ { - char * inputSymbolTable; /* Name of the file containing the - * symbol table from the last link. */ - Tcl_DString linkCommandBuf; /* Command to do the run-time relocation - * of the module.*/ + char * inputSymbolTable; /* Name of the file containing the symbol + * table from the last link. */ + Tcl_DString linkCommandBuf; /* Command to do the run-time relocation of + * the module.*/ char * linkCommand; char relocatedFileName [L_tmpnam]; /* Name of the file holding the relocated */ @@ -166,98 +164,115 @@ TclpDlopen(interp, pathPtr, loadHandle, unloadProcPtr) int status; /* Status return from Tcl_ calls */ char * p; - /* Find the file that contains the symbols for the run-time link. */ - + /* + * Find the file that contains the symbols for the run-time link. + */ + if (SymbolTableFile != NULL) { inputSymbolTable = SymbolTableFile; } else if (tclExecutableName == NULL) { - Tcl_SetResult (interp, "can't find the tclsh executable", TCL_STATIC); + Tcl_SetResult(interp, "can't find the tclsh executable", TCL_STATIC); return TCL_ERROR; } else { inputSymbolTable = tclExecutableName; } - - /* Construct the `ld' command that builds the relocated module */ - - tmpnam (relocatedFileName); - Tcl_DStringInit (&linkCommandBuf); - Tcl_DStringAppend (&linkCommandBuf, "exec ld -o ", -1); - Tcl_DStringAppend (&linkCommandBuf, relocatedFileName, -1); + + /* + * Construct the `ld' command that builds the relocated module. + */ + + tmpnam(relocatedFileName); + Tcl_DStringInit(&linkCommandBuf); + Tcl_DStringAppend(&linkCommandBuf, "exec ld -o ", -1); + Tcl_DStringAppend(&linkCommandBuf, relocatedFileName, -1); #if defined(__mips) || defined(mips) - Tcl_DStringAppend (&linkCommandBuf, " -G 0 ", -1); + Tcl_DStringAppend(&linkCommandBuf, " -G 0 ", -1); #endif - Tcl_DStringAppend (&linkCommandBuf, " -u TclLoadDictionary_", -1); + Tcl_DStringAppend(&linkCommandBuf, " -u TclLoadDictionary_", -1); TclGuessPackageName(Tcl_GetString(pathPtr), &linkCommandBuf); - Tcl_DStringAppend (&linkCommandBuf, " -A ", -1); - Tcl_DStringAppend (&linkCommandBuf, inputSymbolTable, -1); - Tcl_DStringAppend (&linkCommandBuf, " -N -T XXXXXXXX ", -1); - Tcl_DStringAppend (&linkCommandBuf, Tcl_GetString(pathPtr), -1); - Tcl_DStringAppend (&linkCommandBuf, " ", -1); - - if (FindLibraries (interp, pathPtr, &linkCommandBuf) != TCL_OK) { - Tcl_DStringFree (&linkCommandBuf); + Tcl_DStringAppend(&linkCommandBuf, " -A ", -1); + Tcl_DStringAppend(&linkCommandBuf, inputSymbolTable, -1); + Tcl_DStringAppend(&linkCommandBuf, " -N -T XXXXXXXX ", -1); + Tcl_DStringAppend(&linkCommandBuf, Tcl_GetString(pathPtr), -1); + Tcl_DStringAppend(&linkCommandBuf, " ", -1); + + if (FindLibraries(interp, pathPtr, &linkCommandBuf) != TCL_OK) { + Tcl_DStringFree(&linkCommandBuf); return TCL_ERROR; } - - linkCommand = Tcl_DStringValue (&linkCommandBuf); - - /* Determine the starting address, and plug it into the command */ - - startAddress = (char *) (((unsigned long) sbrk (0) - + TCL_LOADSHIM + TCL_LOADALIGN - 1) - & (- TCL_LOADALIGN)); - p = strstr (linkCommand, "-T") + 3; - sprintf (p, "%08lx", (long) startAddress); - p [8] = ' '; - - /* Run the linker */ - - status = Tcl_Eval (interp, linkCommand); - Tcl_DStringFree (&linkCommandBuf); + + linkCommand = Tcl_DStringValue(&linkCommandBuf); + + /* + * Determine the starting address, and plug it into the command. + */ + + startAddress = (char *) (((unsigned long) sbrk(0) + + TCL_LOADSHIM + TCL_LOADALIGN - 1) & (- TCL_LOADALIGN)); + p = strstr(linkCommand, "-T") + 3; + sprintf(p, "%08lx", (long) startAddress); + p[8] = ' '; + + /* + * Run the linker. + */ + + status = Tcl_Eval(interp, linkCommand); + Tcl_DStringFree(&linkCommandBuf); if (status != 0) { return TCL_ERROR; } - - /* Open the linker's result file and read the header */ - - relocatedFd = open (relocatedFileName, O_RDONLY); + + /* + * Open the linker's result file and read the header. + */ + + relocatedFd = open(relocatedFileName, O_RDONLY); if (relocatedFd < 0) { goto ioError; } - status= read (relocatedFd, (char *) & relocatedHead, sizeof relocatedHead); + status = read(relocatedFd, (char *) &relocatedHead, sizeof(relocatedHead)); if (status < sizeof relocatedHead) { goto ioError; } - - /* Check the magic number */ - + + /* + * Check the magic number. + */ + if (relocatedHead.a_magic != OMAGIC) { - Tcl_AppendResult (interp, "bad magic number in intermediate file \"", - relocatedFileName, "\"", (char *) NULL); + Tcl_AppendResult(interp, "bad magic number in intermediate file \"", + relocatedFileName, "\"", (char *) NULL); goto failure; } - - /* Make sure that memory allocation is still consistent */ - - if ((unsigned long) sbrk (0) > (unsigned long) startAddress) { - Tcl_SetResult (interp, "can't load, memory allocation is inconsistent.", - TCL_STATIC); + + /* + * Make sure that memory allocation is still consistent. + */ + + if ((unsigned long) sbrk(0) > (unsigned long) startAddress) { + Tcl_SetResult(interp, "can't load, memory allocation is inconsistent.", + TCL_STATIC); goto failure; } - - /* Make sure that the relocated module's size is reasonable */ - + + /* + * Make sure that the relocated module's size is reasonable. + */ + relocatedSize = relocatedHead.a_text + relocatedHead.a_data - + relocatedHead.a_bss; + + relocatedHead.a_bss; if (relocatedSize > TCL_LOADMAX) { - Tcl_SetResult (interp, "module too big to load", TCL_STATIC); + Tcl_SetResult(interp, "module too big to load", TCL_STATIC); goto failure; } - - /* Advance the break to protect the loaded module */ - - (void) brk (startAddress + relocatedSize); - + + /* + * Advance the break to protect the loaded module. + */ + + (void) brk(startAddress + relocatedSize); + /* * Seek to the start of the module's text. * @@ -266,47 +281,53 @@ TclpDlopen(interp, pathPtr, loadHandle, unloadProcPtr) * dynamically load a binary that is larger than what can fit in * addressable memory is in trouble anyway... */ - + #if defined(__mips) || defined(mips) - status = lseek (relocatedFd, - (off_t) N_TXTOFF (relocatedHead.ex_f, relocatedHead.ex_o), - SEEK_SET); + status = lseek(relocatedFd, + (off_t) N_TXTOFF(relocatedHead.ex_f, relocatedHead.ex_o), + SEEK_SET); #else - status = lseek (relocatedFd, (off_t) N_TXTOFF (relocatedHead), SEEK_SET); + status = lseek(relocatedFd, (off_t) N_TXTOFF (relocatedHead), SEEK_SET); #endif if (status < 0) { goto ioError; } - - /* Read in the module's text and data */ - + + /* + * Read in the module's text and data. + */ + relocatedSize = relocatedHead.a_text + relocatedHead.a_data; - if (read (relocatedFd, startAddress, relocatedSize) < relocatedSize) { - brk (startAddress); - ioError: - Tcl_AppendResult (interp, "error on intermediate file \"", - relocatedFileName, "\": ", Tcl_PosixError (interp), - (char *) NULL); - failure: - (void) unlink (relocatedFileName); + if (read(relocatedFd, startAddress, relocatedSize) < relocatedSize) { + brk(startAddress); + ioError: + Tcl_AppendResult(interp, "error on intermediate file \"", + relocatedFileName, "\": ", Tcl_PosixError(interp), + (char *) NULL); + failure: + (void) unlink(relocatedFileName); return TCL_ERROR; } - - /* Close the intermediate file. */ - - (void) close (relocatedFd); - - /* Arrange things so that intermediate symbol tables eventually get - * deleted. */ - + + /* + * Close the intermediate file. + */ + + (void) close(relocatedFd); + + /* + * Arrange things so that intermediate symbol tables eventually get + * deleted. + */ + if (SymbolTableFile != NULL) { - UnlinkSymbolTable (); + UnlinkSymbolTable(); } else { - atexit (UnlinkSymbolTable); + atexit(UnlinkSymbolTable); } - SymbolTableFile = ckalloc (strlen (relocatedFileName) + 1); - strcpy (SymbolTableFile, relocatedFileName); - + SymbolTableFile = ckalloc(strlen(relocatedFileName) + 1); + strcpy(SymbolTableFile, relocatedFileName); + *loadHandle = startAddress; return TCL_OK; } @@ -316,25 +337,29 @@ TclpDlopen(interp, pathPtr, loadHandle, unloadProcPtr) * * TclpFindSymbol -- * - * Looks up a symbol, by name, through a handle associated with - * a previously loaded piece of code (shared library). + * Looks up a symbol, by name, through a handle associated with a + * previously loaded piece of code (shared library). * * Results: - * Returns a pointer to the function associated with 'symbol' if - * it is found. Otherwise returns NULL and may leave an error - * message in the interp's result. + * Returns a pointer to the function associated with 'symbol' if it is + * found. Otherwise returns NULL and may leave an error message in the + * interp's result. * *---------------------------------------------------------------------- */ Tcl_PackageInitProc* -TclpFindSymbol(interp, loadHandle, symbol) +TclpFindSymbol(interp, loadHandle, symbol) Tcl_Interp *interp; Tcl_LoadHandle loadHandle; CONST char *symbol; { - /* Look up the entry point in the load module's dictionary. */ + /* + * Look up the entry point in the load module's dictionary. + */ + DictFn dictionary = (DictFn) loadHandle; - return (Tcl_PackageInitProc*) dictionary(sym1); + + return (Tcl_PackageInitProc *) dictionary(sym1); } @@ -346,9 +371,9 @@ TclpFindSymbol(interp, loadHandle, symbol) * Find the libraries needed to link a load module at run time. * * Results: - * A standard Tcl completion code. If an error occurs, - * an error message is left in the interp's result. The -l and -L - * flags are concatenated onto the dynamic string `buf'. + * A standard Tcl completion code. If an error occurs, an error message + * is left in the interp's result. The -l and -L flags are concatenated + * onto the dynamic string `buf'. * *------------------------------------------------------------------------ */ @@ -365,53 +390,60 @@ FindLibraries (interp, pathPtr, buf) CONST char *native; char *fileName = Tcl_GetString(pathPtr); - - /* Open the load module */ - + + /* + * Open the load module. + */ + native = Tcl_FSGetNativePath(pathPtr); f = fopen(native, "rb"); /* INTL: Native. */ - + if (f == NULL) { - Tcl_AppendResult (interp, "couldn't open \"", fileName, "\": ", - Tcl_PosixError (interp), (char *) NULL); + Tcl_AppendResult(interp, "couldn't open \"", fileName, "\": ", + Tcl_PosixError(interp), (char *) NULL); return TCL_ERROR; } - - /* Search for the library list in the load module */ - + + /* + * Search for the library list in the load module. + */ + p = "@LIBS: "; - while (*p != '\0' && (c = getc (f)) != EOF) { + while (*p != '\0' && (c = getc(f)) != EOF) { if (c == *p) { ++p; - } - else { + } else { p = "@LIBS: "; if (c == *p) { ++p; } } } - - /* No library list -- this must be an ill-formed module */ - + + /* + * No library list -- this must be an ill-formed module. + */ + if (c == EOF) { - Tcl_AppendResult (interp, "File \"", fileName, - "\" is not a Tcl load module.", (char *) NULL); - (void) fclose (f); + Tcl_AppendResult(interp, "File \"", fileName, + "\" is not a Tcl load module.", (char *) NULL); + (void) fclose(f); return TCL_ERROR; } - - /* Accumulate the library list */ - - while ((c = getc (f)) != '\0' && c != EOF) { + + /* + * Accumulate the library list. + */ + + while ((c = getc(f)) != '\0' && c != EOF) { char cc = c; - Tcl_DStringAppend (buf, &cc, 1); + Tcl_DStringAppend(buf, &cc, 1); } - (void) fclose (f); - + (void) fclose(f); + if (c == EOF) { - Tcl_AppendResult (interp, "Library directory in \"", fileName, - "\" ends prematurely.", (char *) NULL); + Tcl_AppendResult(interp, "Library directory in \"", fileName, + "\" ends prematurely.", (char *) NULL); return TCL_ERROR; } @@ -429,18 +461,18 @@ FindLibraries (interp, pathPtr, buf) * None. * * Side effects: - * The symbol table file from the last dynamic link is removed. - * This function is called when (a) a new symbol table is present - * because another dynamic link is complete, or (b) the process - * is exiting. + * The symbol table file from the last dynamic link is removed. This + * function is called when (a) a new symbol table is present because + * another dynamic link is complete, or (b) the process is exiting. + * *------------------------------------------------------------------------ */ static void -UnlinkSymbolTable () +UnlinkSymbolTable() { - (void) unlink (SymbolTableFile); - ckfree (SymbolTableFile); + (void) unlink(SymbolTableFile); + ckfree(SymbolTableFile); SymbolTableFile = NULL; } @@ -449,9 +481,9 @@ UnlinkSymbolTable () * * TclpUnloadFile -- * - * Unloads a dynamically loaded binary code file from memory. - * Code pointers in the formerly loaded file are no longer valid - * after calling this function. + * Unloads a dynamically loaded binary code file from memory. Code + * pointers in the formerly loaded file are no longer valid after calling + * this function. * * Results: * None. @@ -464,10 +496,9 @@ UnlinkSymbolTable () void TclpUnloadFile(loadHandle) - Tcl_LoadHandle loadHandle; /* loadHandle returned by a previous call - * to TclpDlopen(). The loadHandle is - * a token that represents the loaded - * file. */ + Tcl_LoadHandle loadHandle; /* loadHandle returned by a previous call to + * TclpDlopen(). The loadHandle is a token + * that represents the loaded file. */ { } @@ -476,14 +507,14 @@ TclpUnloadFile(loadHandle) * * TclGuessPackageName -- * - * If the "load" command is invoked without providing a package - * name, this procedure is invoked to try to figure it out. + * If the "load" command is invoked without providing a package name, + * this procedure is invoked to try to figure it out. * * Results: - * Always returns 0 to indicate that we couldn't figure out a - * package name; generic code will then try to guess the package - * from the file name. A return value of 1 would have meant that - * we figured out the package name and put it in bufPtr. + * Always returns 0 to indicate that we couldn't figure out a package + * name; generic code will then try to guess the package from the file + * name. A return value of 1 would have meant that we figured out the + * package name and put it in bufPtr. * * Side effects: * None. @@ -495,8 +526,8 @@ int TclGuessPackageName(fileName, bufPtr) CONST char *fileName; /* Name of file containing package (already * translated to local form if needed). */ - Tcl_DString *bufPtr; /* Initialized empty dstring. Append - * package name to this if possible. */ + Tcl_DString *bufPtr; /* Initialized empty dstring. Append package + * name to this if possible. */ { CONST char *p, *q; char *r; @@ -534,3 +565,11 @@ TclGuessPackageName(fileName, bufPtr) return 1; } + +/* + * Local Variables: + * mode: c + * c-basic-offset: 4 + * fill-column: 78 + * End: + */ |