X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/68db017386579f2c100e606df13934378286271e..6dc5c8a75b8ad0aea911c0236e4fdb35e1e0839f:/src/unexec.c diff --git a/src/unexec.c b/src/unexec.c index 3be336a9a7..7fe7e26568 100644 --- a/src/unexec.c +++ b/src/unexec.c @@ -1,4 +1,5 @@ -/* Copyright (C) 1985,86,87,88,92,93,94 Free Software Foundation, Inc. +/* Copyright (C) 1985, 1986, 1987, 1988, 1992, 1993, 1994, 2002, 2003, 2004, + 2005, 2006 Free Software Foundation, Inc. This file is part of GNU Emacs. @@ -14,7 +15,8 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Emacs; see the file COPYING. If not, write to -the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ +the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, +Boston, MA 02110-1301, USA. */ /* @@ -133,7 +135,7 @@ before writing it (above and beyond the number of bytes of actual program text). HDR's standard fields are already correct, except that this adjustment to the `a_text' field has not yet been made; thus, the amount of offset can depend on the data in the file. - + * A_TEXT_SEEK(HDR) If defined, this macro specifies the number of bytes to seek into the @@ -170,12 +172,14 @@ pointer looks like an int) but not on all machines. #ifndef CANNOT_DUMP /* all rest of file! */ -#ifdef COFF_ENCAPSULATE -int need_coff_header = 1; -#include /* The location might be a poor assumption */ -#else -#ifdef MSDOS +#if defined(COFF) && defined(HAVE_COFF_H) #include +#ifdef MSDOS +#if __DJGPP__ > 1 +#include /* for O_RDONLY, O_RDWR */ +#include /* for _crt0_startup_flags and its bits */ +static int save_djgpp_startup_flags; +#endif /* __DJGPP__ > 1 */ #define filehdr external_filehdr #define scnhdr external_scnhdr #define syment external_syment @@ -193,12 +197,15 @@ struct aouthdr unsigned long text_start;/* base of text used for this file */ unsigned long data_start;/* base of data used for this file */ }; - - -#else /* not MSDOS */ -#include #endif /* not MSDOS */ -#endif +#else /* not COFF */ +#ifdef COFF_ENCAPSULATE +int need_coff_header = 1; +#include /* The location might be a poor assumption */ +#else /* not COFF_ENCAPSULATE */ +#include +#endif /* not COFF_ENCAPSULATE */ +#endif /* not COFF */ /* Define getpagesize if the system does not. Note that this may depend on symbols defined in a.out.h. */ @@ -239,6 +246,8 @@ long lnnoptr; /* Pointer to line-number info within file */ static long text_scnptr; static long data_scnptr; +static long coff_offset; + #else /* not COFF */ #ifdef HPUX @@ -280,7 +289,7 @@ static EXEC_HDR_TYPE hdr, ohdr; #else /* not HPUX */ -#if defined (USG) && !defined (IBMAIX) && !defined (IRIS) && !defined (COFF_ENCAPSULATE) && !defined (LINUX) +#if defined (USG) && !defined (IBMAIX) && !defined (IRIS) && !defined (COFF_ENCAPSULATE) && !defined (GNU_LINUX) static struct bhdr hdr, ohdr; #define a_magic fmagic #define a_text tsize @@ -359,48 +368,6 @@ static int copy_text_and_data (); static int copy_sym (); static void mark_x (); -/* **************************************************************** - * unexec - * - * driving logic. - */ -unexec (new_name, a_name, data_start, bss_start, entry_address) - char *new_name, *a_name; - unsigned data_start, bss_start, entry_address; -{ - int new, a_out = -1; - - if (a_name && (a_out = open (a_name, O_RDONLY)) < 0) - { - PERROR (a_name); - } - if ((new = creat (new_name, 0666)) < 0) - { - PERROR (new_name); - } - - if (make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) < 0 - || copy_text_and_data (new, a_out) < 0 - || copy_sym (new, a_out, a_name, new_name) < 0 -#ifdef COFF -#ifndef COFF_BSD_SYMBOLS - || adjust_lnnoptrs (new, a_out, new_name) < 0 -#endif -#endif - ) - { - close (new); - /* unlink (new_name); /* Failed, unlink new a.out */ - return -1; - } - - close (new); - if (a_out >= 0) - close (a_out); - mark_x (new_name); - return 0; -} - /* **************************************************************** * make_hdr * @@ -470,9 +437,32 @@ make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) } #ifdef COFF + coff_offset = 0L; /* stays zero, except in DJGPP */ + /* Salvage as much info from the existing file as possible */ if (a_out >= 0) { +#ifdef MSDOS +#if __DJGPP__ > 1 + /* Support the coff-go32-exe format with a prepended stub, since + this is what GCC 2.8.0 and later generates by default in DJGPP. */ + unsigned short mz_header[3]; + + if (read (a_out, &mz_header, sizeof (mz_header)) != sizeof (mz_header)) + { + PERROR (a_name); + } + if (mz_header[0] == 0x5a4d || mz_header[0] == 0x4d5a) /* "MZ" or "ZM" */ + { + coff_offset = (long)mz_header[2] * 512L; + if (mz_header[1]) + coff_offset += (long)mz_header[1] - 512L; + lseek (a_out, coff_offset, 0); + } + else + lseek (a_out, 0L, 0); +#endif /* __DJGPP__ > 1 */ +#endif /* MSDOS */ if (read (a_out, &f_hdr, sizeof (f_hdr)) != sizeof (f_hdr)) { PERROR (a_name); @@ -487,7 +477,7 @@ make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) block_copy_start += sizeof (f_ohdr); } /* Loop through section headers, copying them in */ - lseek (a_out, sizeof (f_hdr) + f_hdr.f_opthdr, 0); + lseek (a_out, coff_offset + sizeof (f_hdr) + f_hdr.f_opthdr, 0); for (scns = f_hdr.f_nscns; scns > 0; scns--) { if (read (a_out, &scntemp, sizeof (scntemp)) != sizeof (scntemp)) { @@ -790,7 +780,7 @@ make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) PERROR (new_name); } -#if 0 /* This #ifndef caused a bug on Linux when using QMAGIC. */ +#if 0 /* This #ifndef caused a bug on GNU/Linux when using QMAGIC. */ /* This adjustment was done above only #ifndef NO_REMAP, so only undo it now #ifndef NO_REMAP. */ /* #ifndef NO_REMAP */ @@ -804,6 +794,61 @@ make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) #endif /* not COFF */ } +write_segment (new, ptr, end) + int new; + register char *ptr, *end; +{ + register int i, nwrite, ret; + char buf[80]; +#ifndef USE_CRT_DLL + extern int errno; +#endif + /* This is the normal amount to write at once. + It is the size of block that NFS uses. */ + int writesize = 1 << 13; + int pagesize = getpagesize (); + char zeros[1 << 13]; + + bzero (zeros, sizeof (zeros)); + + for (i = 0; ptr < end;) + { + /* Distance to next multiple of writesize. */ + nwrite = (((int) ptr + writesize) & -writesize) - (int) ptr; + /* But not beyond specified end. */ + if (nwrite > end - ptr) nwrite = end - ptr; + ret = write (new, ptr, nwrite); + /* If write gets a page fault, it means we reached + a gap between the old text segment and the old data segment. + This gap has probably been remapped into part of the text segment. + So write zeros for it. */ + if (ret == -1 +#ifdef EFAULT + && errno == EFAULT +#endif + ) + { + /* Write only a page of zeros at once, + so that we we don't overshoot the start + of the valid memory in the old data segment. */ + if (nwrite > pagesize) + nwrite = pagesize; + write (new, zeros, nwrite); + } +#if 0 /* Now that we have can ask `write' to write more than a page, + it is legit for write do less than the whole amount specified. */ + else if (nwrite != ret) + { + sprintf (buf, + "unexec write failure: addr 0x%x, fileno %d, size 0x%x, wrote 0x%x, errno %d", + ptr, new, nwrite, ret, errno); + PERROR (buf); + } +#endif + i += nwrite; + ptr += nwrite; + } +} /* **************************************************************** * copy_text_and_data * @@ -875,6 +920,19 @@ copy_text_and_data (new, a_out) #else /* COFF, but not USG_SHARED_LIBRARIES */ +#ifdef MSDOS +#if __DJGPP__ >= 2 + /* Dump the original table of exception handlers, not the one + where our exception hooks are registered. */ + __djgpp_exception_toggle (); + + /* Switch off startup flags that might have been set at runtime + and which might change the way that dumped Emacs works. */ + save_djgpp_startup_flags = _crt0_startup_flags; + _crt0_startup_flags &= ~(_CRT0_FLAG_NO_LFN | _CRT0_FLAG_NEARPTR); +#endif +#endif + lseek (new, (long) text_scnptr, 0); ptr = (char *) f_ohdr.text_start; #ifdef HEADER_INCL_IN_TEXT @@ -889,6 +947,16 @@ copy_text_and_data (new, a_out) end = ptr + f_ohdr.dsize; write_segment (new, ptr, end); +#ifdef MSDOS +#if __DJGPP__ >= 2 + /* Restore our exception hooks. */ + __djgpp_exception_toggle (); + + /* Restore the startup flags. */ + _crt0_startup_flags = save_djgpp_startup_flags; +#endif +#endif + #endif /* USG_SHARED_LIBRARIES */ #else /* if not COFF */ @@ -915,8 +983,8 @@ copy_text_and_data (new, a_out) * runs, it copies the table to where these parameters live during * execution. This data is in text space, so it cannot be modified here * before saving the executable, so the data is written manually. In - * addition, the table does not have a label, and the nearest accessable - * label (mcount) is not prefixed with a '_', thus making it inaccessable + * addition, the table does not have a label, and the nearest accessible + * label (mcount) is not prefixed with a '_', thus making it inaccessible * from within C programs. To overcome this, emacs's executable is passed * through the command 'nm %s | fgrep mcount' into a pipe, and the * resultant output is then used to find the address of 'mcount'. As far as @@ -938,7 +1006,7 @@ copy_text_and_data (new, a_out) char c; int mcount_address, mcount_offset, count; extern char *_execname; - + /* The use of _execname is incompatible with RISCiX 1.1 */ sprintf (command, "nm %s | fgrep mcount", _execname); @@ -958,7 +1026,7 @@ copy_text_and_data (new, a_out) { sprintf (errbuf, "Failed to execute the command '%s'\n", command); PERROR (errbuf); - } + } sscanf(address_text, "%x", &mcount_address); ptr = (char *) unexec_text_start; @@ -1006,47 +1074,6 @@ copy_text_and_data (new, a_out) return 0; } - -write_segment (new, ptr, end) - int new; - register char *ptr, *end; -{ - register int i, nwrite, ret; - char buf[80]; - extern int errno; - int pagesize = getpagesize (); - char *zeros = (char *) alloca (pagesize); - - bzero (zeros, pagesize); - - for (i = 0; ptr < end;) - { - /* distance to next multiple of pagesize. */ - nwrite = (((int) ptr + pagesize) & -pagesize) - (int) ptr; - /* But not beyond specified end. */ - if (nwrite > end - ptr) nwrite = end - ptr; - ret = write (new, ptr, nwrite); - /* If write gets a page fault, it means we reached - a gap between the old text segment and the old data segment. - This gap has probably been remapped into part of the text segment. - So write zeros for it. */ - if (ret == -1 -#ifdef EFAULT - && errno == EFAULT -#endif - ) - write (new, zeros, nwrite); - else if (nwrite != ret) - { - sprintf (buf, - "unexec write failure: addr 0x%x, fileno %d, size 0x%x, wrote 0x%x, errno %d", - ptr, new, nwrite, ret, errno); - PERROR (buf); - } - i += nwrite; - ptr += nwrite; - } -} /* **************************************************************** * copy_sym @@ -1071,10 +1098,12 @@ copy_sym (new, a_out, a_name, new_name) #ifdef COFF if (lnnoptr) /* if there is line number info */ - lseek (a_out, lnnoptr, 0); /* start copying from there */ + lseek (a_out, coff_offset + lnnoptr, 0); /* start copying from there */ else -#endif /* COFF */ - lseek (a_out, SYMS_START, 0); /* Position a.out to symtab. */ + lseek (a_out, coff_offset + SYMS_START, 0); /* Position a.out to symtab. */ +#else /* not COFF */ + lseek (a_out, SYMS_START, 0); /* Position a.out to symtab. */ +#endif /* not COFF */ while ((n = read (a_out, page, sizeof page)) > 0) { @@ -1193,4 +1222,49 @@ adjust_lnnoptrs (writedesc, readdesc, new_name) #endif /* COFF */ +/* **************************************************************** + * unexec + * + * driving logic. + */ +unexec (new_name, a_name, data_start, bss_start, entry_address) + char *new_name, *a_name; + unsigned data_start, bss_start, entry_address; +{ + int new, a_out = -1; + + if (a_name && (a_out = open (a_name, O_RDONLY)) < 0) + { + PERROR (a_name); + } + if ((new = creat (new_name, 0666)) < 0) + { + PERROR (new_name); + } + + if (make_hdr (new, a_out, data_start, bss_start, entry_address, a_name, new_name) < 0 + || copy_text_and_data (new, a_out) < 0 + || copy_sym (new, a_out, a_name, new_name) < 0 +#ifdef COFF +#ifndef COFF_BSD_SYMBOLS + || adjust_lnnoptrs (new, a_out, new_name) < 0 +#endif +#endif + ) + { + close (new); + /* unlink (new_name); /* Failed, unlink new a.out */ + return -1; + } + + close (new); + if (a_out >= 0) + close (a_out); + mark_x (new_name); + return 0; +} + #endif /* not CANNOT_DUMP */ + +/* arch-tag: 62409b69-e27a-4a7c-9413-0210d6b54e7f + (do not change this comment) */