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author | Robert de Bath <rdebath@poboxes.com> | 1996-12-01 16:58:31 +0100 |
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committer | Lubomir Rintel <lkundrak@v3.sk> | 2013-10-23 23:34:16 +0200 |
commit | f8de35da65c5d93bb733073cf40da154bc1c0748 (patch) | |
tree | d28c7644739a24402376d24cb0020ea410a9ccff /libc/syscall/exec.c | |
parent | c218c617b5be443b7968308506969ad2b726d73c (diff) | |
download | dev86-f8de35da65c5d93bb733073cf40da154bc1c0748.tar.gz |
Import Dev86src-0.0.9.tar.gzv0.0.9
Diffstat (limited to 'libc/syscall/exec.c')
-rw-r--r-- | libc/syscall/exec.c | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/libc/syscall/exec.c b/libc/syscall/exec.c new file mode 100644 index 0000000..411b744 --- /dev/null +++ b/libc/syscall/exec.c @@ -0,0 +1,292 @@ + +#include <errno.h> +#include <sys/stat.h> + +extern char ** environ; + +#ifdef L_execl +int +execl(fname, arg0) +char * fname, *arg0; +{ + return execve(fname, &arg0, environ); +} +#endif + +#ifdef L_execv +int +execv(fname, argv) +char * fname, **argv; +{ + return execve(fname, argv, environ); +} +#endif + +#ifdef L_execle +int +execle(fname, arg0) +char *fname, *arg0; +{ + char ** envp = &arg0; + while(*envp) envp++; + return execve(fname, &arg0, envp+1); +} +#endif + +#ifdef L_execve +int +execve(fname, argv, envp) +char * fname; +char ** argv; +char ** envp; +{ + char **p; + int argv_len=0, argv_count=0; + int envp_len=0, envp_count=0; + int stack_bytes; + unsigned short * pip; + char * pcp, * stk_ptr, *baseoff; + int rv; + + /* How much space for argv */ + for(p=argv; p && *p && argv_len >= 0; p++) + { + argv_count++; argv_len += strlen(*p)+1; + } + + /* How much space for envp */ + for(p=envp; p && *p && envp_len >= 0; p++) + { + envp_count++; envp_len += strlen(*p)+1; + } + + /* tot it all up */ + stack_bytes = 2 /* argc */ + + argv_count * 2 + 2 /* argv */ + + argv_len + + envp_count * 2 + 2 /* envp */ + + envp_len; + + /* Allocate it */ + if( argv_len < 0 || envp_len < 0 || stack_bytes <= 0 + || (int)(stk_ptr = (char*)sbrk(stack_bytes)) == -1) + { + errno = ENOMEM; + return -1; + } + +/* Sanity check + printf("Argv = (%d,%d), Envp=(%d,%d), stack=%d\n", + argv_count, argv_len, envp_count, envp_len, stack_bytes); +*/ + + /* Now copy in the strings */ + pip=(unsigned short *) stk_ptr; + pcp=stk_ptr+2*(1+argv_count+1+envp_count+1); + + /* baseoff = stk_ptr + stack_bytes; */ + baseoff = stk_ptr; + *pip++ = argv_count; + for(p=argv; p && *p; p++) + { + int l; + *pip++ = pcp-baseoff; + l = strlen(*p)+1; + memcpy(pcp, *p, l); + pcp += l; + } + *pip++ = 0; + + for(p=envp; p && *p; p++) + { + int l; + *pip++ = pcp-baseoff; + l = strlen(*p)+1; + memcpy(pcp, *p, l); + pcp += l; + } + *pip++ = 0; + + rv = __exec(fname, stk_ptr, stack_bytes); + /* FIXME: This will probably have to interpret '#!' style exe's */ + sbrk(-stack_bytes); + return rv; +} +#endif + +#ifdef L_execlp +int +execlp(fname, arg0) +char * fname, *arg0; +{ + return execvp(fname, &arg0); +} +#endif + +#ifdef L_execvp +int +execvp(fname, argv) +char * fname, **argv; +{ + char *pname = fname, *path; + int besterr = ENOENT; + int flen, plen; + char * bp = sbrk(0); + + if( *fname != '/' && (path = getenv("PATH")) != 0 ) + { + flen = strlen(fname)+2; + + for(;path;) + { + if( *path == ':' || *path == '\0' ) + { + tryrun(fname, argv); + if( errno == EACCES ) besterr = EACCES; + if( *path ) path++; else break; + } + else + { + char * p = strchr(path, ':'); + if(p) *p = '\0'; + plen = strlen(path); + pname = sbrk(plen+flen); + + strcpy(pname, path); + strcat(pname, "/"); + strcat(pname, fname); + + tryrun(pname, argv); + if( errno == EACCES ) besterr = EACCES; + + brk(pname); + pname = fname; + if(p) *p++ = ':'; + path=p; + } + } + } + + tryrun(pname, argv); + brk(bp); + if( errno == ENOENT || errno == 0 ) errno = besterr; + return -1; +} + +static int tryrun(pname, argv) +char * pname; +char ** argv; +{ +static char *shprog[] = {"/bin/sh", "", 0}; + struct stat st; + + if( stat(pname, &st) < 0 ) return; + if( !S_ISREG(st.st_mode) ) return; + +#ifdef __AS386_16__ + __execvve(pname, (void*)0, argv, environ); + if( errno == ENOEXEC ) + { + shprog[1] = pname; + __execvve(shprog[0], shprog, argv, environ); + } +#else + execve(pname, argv, environ); + /* FIXME - running /bin/sh in 386 mode */ +#endif +} + +#ifdef __AS386_16__ +static int +__execvve(fname, interp, argv, envp) +char * fname; +char ** interp; +char ** argv; +char ** envp; +{ + char **p; + int argv_len=0, argv_count=0; + int envp_len=0, envp_count=0; + int stack_bytes; + unsigned short * pip; + char * pcp, * stk_ptr, *baseoff; + int rv; + + /* How much space for argv */ + for(p=interp; p && *p && argv_len >= 0; p++) + { + argv_count++; argv_len += strlen(*p)+1; + } + for(p=argv; p && *p && argv_len >= 0; p++) + { + argv_count++; argv_len += strlen(*p)+1; + } + + /* How much space for envp */ + for(p=envp; p && *p && envp_len >= 0; p++) + { + envp_count++; envp_len += strlen(*p)+1; + } + + /* tot it all up */ + stack_bytes = 2 /* argc */ + + argv_count * 2 + 2 /* argv */ + + argv_len + + envp_count * 2 + 2 /* envp */ + + envp_len; + + /* Allocate it */ + if( argv_len < 0 || envp_len < 0 || stack_bytes <= 0 + || (int)(stk_ptr = (char*)sbrk(stack_bytes)) == -1) + { + errno = ENOMEM; + return -1; + } + +/* Sanity check + printf("Argv = (%d,%d), Envp=(%d,%d), stack=%d\n", + argv_count, argv_len, envp_count, envp_len, stack_bytes); +*/ + + /* Now copy in the strings */ + pip=(unsigned short *) stk_ptr; + pcp=stk_ptr+2*(1+argv_count+1+envp_count+1); + + /* baseoff = stk_ptr + stack_bytes; */ + baseoff = stk_ptr; + *pip++ = argv_count; + for(p=interp; p && *p; p++) + { + int l; + *pip++ = pcp-baseoff; + l = strlen(*p)+1; + memcpy(pcp, *p, l); + pcp += l; + } + for(p=argv; p && *p; p++) + { + int l; + *pip++ = pcp-baseoff; + l = strlen(*p)+1; + memcpy(pcp, *p, l); + pcp += l; + } + *pip++ = 0; + + for(p=envp; p && *p; p++) + { + int l; + *pip++ = pcp-baseoff; + l = strlen(*p)+1; + memcpy(pcp, *p, l); + pcp += l; + } + *pip++ = 0; + + rv = __exec(fname, stk_ptr, stack_bytes); + /* FIXME: This will probably have to interpret '#!' style exe's */ + sbrk(-stack_bytes); + return rv; +} +#endif +#endif |