diff options
Diffstat (limited to 'lib/csu/i386/crt0.c')
| -rw-r--r-- | lib/csu/i386/crt0.c | 348 |
1 files changed, 308 insertions, 40 deletions
diff --git a/lib/csu/i386/crt0.c b/lib/csu/i386/crt0.c index 363098b..38fd64c 100644 --- a/lib/csu/i386/crt0.c +++ b/lib/csu/i386/crt0.c @@ -1,5 +1,5 @@ -/*- - * Copyright (c) 1990 The Regents of the University of California. +/* + * Copyright (c) 1993 Paul Kranenburg * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -12,50 +12,105 @@ * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: - * This product includes software developed by the University of - * California, Berkeley and its contributors. - * 4. Neither the name of the University nor the names of its contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. + * This product includes software developed by Paul Kranenburg. + * 4. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * - * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND - * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE - * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE - * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE - * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT - * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY - * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF - * SUCH DAMAGE. + * $Id: crt0.c,v 1.8 1994/02/13 20:53:11 jkh Exp $ */ + #if defined(LIBC_SCCS) && !defined(lint) -static char sccsid[] = "@(#)crt0.c 5.7 (Berkeley) 7/3/91"; +static char sccsid[] = "%W% (Erasmus) %G%"; #endif /* LIBC_SCCS and not lint */ +extern void exit(); +int _callmain(); -/* - * C start up routine. - * Robert Henry, UCB, 20 Oct 81 - * - * We make the following (true) assumption: - * 1) The only register variable that we can trust is the frame pointer, - * ebp, which points to the base of the kernel calling frame. - */ +#include <sys/param.h> + +#ifdef DYNAMIC +#include <sys/types.h> +#include <sys/syscall.h> +#include <a.out.h> +#ifndef N_GETMAGIC +#define N_GETMAGIC(x) ((x).a_magic) +#endif +#ifndef N_BSSADDR +#define N_BSSADDR(x) (N_DATADDR(x)+(x).a_data) +#endif +#include <sys/mman.h> +#ifdef sun +#define MAP_COPY MAP_PRIVATE +#define MAP_FILE 0 +#define MAP_ANON 0 +#endif +#include <link.h> + +extern struct _dynamic _DYNAMIC; +static struct ld_entry *ld_entry; +static void __do_dynamic_link (); +static char *_getenv(); +static int _strncmp(); + +#ifdef sun +#define LDSO "/usr/lib/ld.so" +#endif +#ifdef BSD +#define LDSO "/usr/libexec/ld.so" +#endif -char **environ = (char **)0; -int errno = 0; +#endif /* DYNAMIC */ -asm(".text"); -asm(".long 0xc000c000"); +static char *_strrchr(); +char **environ; + +#ifdef BSD extern unsigned char etext; extern unsigned char eprol asm ("eprol"); extern start() asm("start"); extern mcount() asm ("mcount"); +int errno; +static char empty[1]; +char *__progname = empty; +#endif + +/* + * We need these system calls, but can't use library stubs + */ +#define _exit(v) __syscall(SYS_exit, (v)) +#define open(name, f, m) __syscall(SYS_open, (name), (f), (m)) +#define close(fd) __syscall(SYS_close, (fd)) +#define read(fd, s, n) __syscall(SYS_read, (fd), (s), (n)) +#define write(fd, s, n) __syscall(SYS_write, (fd), (s), (n)) +#define dup(fd) __syscall(SYS_dup, (fd)) +#define dup2(fd, fdnew) __syscall(SYS_dup2, (fd), (fdnew)) +#ifdef sun +#define mmap(addr, len, prot, flags, fd, off) \ + __syscall(SYS_mmap, (addr), (len), (prot), _MAP_NEW|(flags), (fd), (off)) +#else +#define mmap(addr, len, prot, flags, fd, off) \ + __syscall(SYS_mmap, (addr), (len), (prot), (flags), (fd), (off)) +#endif + +#define _FATAL(str) \ + write(2, str, sizeof(str)), \ + _exit(1); + + start() { struct kframe { @@ -71,38 +126,251 @@ start() register char **targv; register char **argv; extern void _mcleanup(); +#ifdef DYNAMIC + volatile caddr_t x; +#endif #ifdef lint kfp = 0; initcode = initcode = 0; -#else not lint +#else /* not lint */ /* just above the saved frame pointer */ asm ("lea 4(%%ebp), %0" : "=r" (kfp) ); -#endif not lint +#endif /* not lint */ for (argv = targv = &kfp->kargv[0]; *targv++; /* void */) /* void */ ; if (targv >= (char **)(*argv)) --targv; environ = targv; + + if (argv[0]) + if ((__progname = _strrchr(argv[0], '/')) == NULL) + __progname = argv[0]; + else + ++__progname; + +#ifdef DYNAMIC + /* ld(1) convention: if DYNAMIC = 0 then statically linked */ +#ifdef stupid_gcc + if (&_DYNAMIC) + __do_dynamic_link(); +#else + x = (caddr_t)&_DYNAMIC; + if (x) + __do_dynamic_link(); +#endif +#endif /* DYNAMIC */ + asm("eprol:"); #ifdef MCRT0 atexit(_mcleanup); monstartup(&eprol, &etext); #endif MCRT0 + +asm ("__callmain:"); /* Defined for the benefit of debuggers */ exit(main(kfp->kargc, argv, environ)); } -#ifdef CRT0 +#ifdef DYNAMIC +static void +__do_dynamic_link () +{ + struct crt_ldso crt; + struct exec hdr; + char *ldso; + int dupzfd; + int (*entry)(); + +#ifdef DEBUG + /* Provision for alternate ld.so - security risk! */ + if (!(ldso = _getenv("LDSO"))) +#endif + ldso = LDSO; + + crt.crt_ldfd = open(ldso, 0, 0); + if (crt.crt_ldfd == -1) { + _FATAL("No ld.so\n"); + } + + /* Read LDSO exec header */ + if (read(crt.crt_ldfd, &hdr, sizeof hdr) < sizeof hdr) { + _FATAL("Failure reading ld.so\n"); + } + if ((N_GETMAGIC_NET(hdr) != ZMAGIC) && (N_GETMAGIC(hdr) != QMAGIC)) { + _FATAL("Bad magic: ld.so\n"); + } + + /* We use MAP_ANON */ + crt.crt_dzfd = -1; + + /* Map in ld.so */ + crt.crt_ba = mmap(0, hdr.a_text, + PROT_READ|PROT_EXEC, + MAP_FILE|MAP_COPY, + crt.crt_ldfd, N_TXTOFF(hdr)); + if (crt.crt_ba == -1) { + _FATAL("Cannot map ld.so\n"); + } + +#ifdef BSD +/* !!! + * This is gross, ld.so is a ZMAGIC a.out, but has `sizeof(hdr)' for + * an entry point and not at PAGSIZ as the N_*ADDR macros assume. + */ +#undef N_DATADDR +#undef N_BSSADDR +#define N_DATADDR(x) ((x).a_text) +#define N_BSSADDR(x) ((x).a_text + (x).a_data) +#endif + + /* Map in data segment of ld.so writable */ + if (mmap(crt.crt_ba+N_DATADDR(hdr), hdr.a_data, + PROT_READ|PROT_WRITE, + MAP_FIXED|MAP_FILE|MAP_COPY, + crt.crt_ldfd, N_DATOFF(hdr)) == -1) { + _FATAL("Cannot map ld.so\n"); + } + + /* Map bss segment of ld.so zero */ + if (hdr.a_bss && mmap(crt.crt_ba+N_BSSADDR(hdr), hdr.a_bss, + PROT_READ|PROT_WRITE, + MAP_FIXED|MAP_ANON|MAP_COPY, + crt.crt_dzfd, 0) == -1) { + _FATAL("Cannot map ld.so\n"); + } + + crt.crt_dp = &_DYNAMIC; + crt.crt_ep = environ; + crt.crt_bp = (caddr_t)_callmain; + crt.crt_prog = __progname; + + entry = (int (*)())(crt.crt_ba + sizeof hdr); + if ((*entry)(CRT_VERSION_BSD_3, &crt) == -1) { + _FATAL("ld.so failed\n"); + } + + ld_entry = _DYNAMIC.d_entry; + return; +} + /* - * null mcount and moncontrol, - * just in case some routine is compiled for profiling + * DL stubs */ -moncontrol(val) - int val; + +void * +dlopen(name, mode) +char *name; +int mode; { + if (ld_entry == NULL) + return NULL; + return (ld_entry->dlopen)(name, mode); } -mcount() { } -#endif CRT0 +int +dlclose(fd) +void *fd; +{ + if (ld_entry == NULL) + return -1; + + return (ld_entry->dlclose)(fd); +} + +void * +dlsym(fd, name) +void *fd; +char *name; +{ + if (ld_entry == NULL) + return NULL; + + return (ld_entry->dlsym)(fd, name); +} + +int +dlctl(fd, cmd, arg) +void *fd, *arg; +int cmd; +{ + if (ld_entry == NULL) + return -1; + + return (ld_entry->dlctl)(fd, cmd, arg); +} + +/* + * Support routines + */ + +static int +_strncmp(s1, s2, n) + register char *s1, *s2; + register n; +{ + + if (n == 0) + return (0); + do { + if (*s1 != *s2++) + return (*(unsigned char *)s1 - *(unsigned char *)--s2); + if (*s1++ == 0) + break; + } while (--n != 0); + return (0); +} + +static char * +_getenv(name) + register char *name; +{ + extern char **environ; + register int len; + register char **P, *C; + + for (C = name, len = 0; *C && *C != '='; ++C, ++len); + for (P = environ; *P; ++P) + if (!_strncmp(*P, name, len)) + if (*(C = *P + len) == '=') { + return(++C); + } + return (char *)0; +} + + asm(" ___syscall:"); + asm(" popl %ecx"); + asm(" popl %eax"); + asm(" pushl %ecx"); + asm(" .byte 0x9a"); + asm(" .long 0"); + asm(" .word 7"); + asm(" pushl %ecx"); + asm(" jc 1f"); + asm(" ret"); + asm(" 1:"); + asm(" movl $-1,%eax"); + asm(" ret"); + +#endif /* DYNAMIC */ + +static char * +_strrchr(p, ch) +register char *p, ch; +{ + register char *save; + + for (save = NULL;; ++p) { + if (*p == ch) + save = (char *)p; + if (!*p) + return(save); + } +/* NOTREACHED */ +} + +#ifdef MCRT0 +asm (" .text"); +asm ("_eprol:"); +#endif |
