Config_70-01: Remove default "/share"
[p5sagit/p5-mst-13.2.git] / os2 / os2.c
index 701bb52..d545703 100644 (file)
--- a/os2/os2.c
+++ b/os2/os2.c
 #include "EXTERN.h"
 #include "perl.h"
 
+#ifdef USE_THREADS
+
+typedef void (*emx_startroutine)(void *);
+typedef void* (*pthreads_startroutine)(void *);
+
+enum pthreads_state {
+    pthreads_st_none = 0, 
+    pthreads_st_run,
+    pthreads_st_exited, 
+    pthreads_st_detached, 
+    pthreads_st_waited,
+};
+const char *pthreads_states[] = {
+    "uninit",
+    "running",
+    "exited",
+    "detached",
+    "waited for",
+};
+
+typedef struct {
+    void *status;
+    perl_cond cond;
+    enum pthreads_state state;
+} thread_join_t;
+
+thread_join_t *thread_join_data;
+int thread_join_count;
+perl_mutex start_thread_mutex;
+
+int
+pthread_join(perl_os_thread tid, void **status)
+{
+    MUTEX_LOCK(&start_thread_mutex);
+    switch (thread_join_data[tid].state) {
+    case pthreads_st_exited:
+       thread_join_data[tid].state = pthreads_st_none; /* Ready to reuse */
+       MUTEX_UNLOCK(&start_thread_mutex);
+       *status = thread_join_data[tid].status;
+       break;
+    case pthreads_st_waited:
+       MUTEX_UNLOCK(&start_thread_mutex);
+       croak("join with a thread with a waiter");
+       break;
+    case pthreads_st_run:
+       thread_join_data[tid].state = pthreads_st_waited;
+       COND_INIT(&thread_join_data[tid].cond);
+       MUTEX_UNLOCK(&start_thread_mutex);
+       COND_WAIT(&thread_join_data[tid].cond, NULL);    
+       COND_DESTROY(&thread_join_data[tid].cond);
+       thread_join_data[tid].state = pthreads_st_none; /* Ready to reuse */
+       *status = thread_join_data[tid].status;
+       break;
+    default:
+       MUTEX_UNLOCK(&start_thread_mutex);
+       croak("join: unknown thread state: '%s'", 
+             pthreads_states[thread_join_data[tid].state]);
+       break;
+    }
+    return 0;
+}
+
+void
+pthread_startit(void *arg)
+{
+    /* Thread is already started, we need to transfer control only */
+    pthreads_startroutine start_routine = *((pthreads_startroutine*)arg);
+    int tid = pthread_self();
+    void *retval;
+    
+    arg = ((void**)arg)[1];
+    if (tid >= thread_join_count) {
+       int oc = thread_join_count;
+       
+       thread_join_count = tid + 5 + tid/5;
+       if (thread_join_data) {
+           Renew(thread_join_data, thread_join_count, thread_join_t);
+           Zero(thread_join_data + oc, thread_join_count - oc, thread_join_t);
+       } else {
+           Newz(1323, thread_join_data, thread_join_count, thread_join_t);
+       }
+    }
+    if (thread_join_data[tid].state != pthreads_st_none)
+       croak("attempt to reuse thread id %i", tid);
+    thread_join_data[tid].state = pthreads_st_run;
+    /* Now that we copied/updated the guys, we may release the caller... */
+    MUTEX_UNLOCK(&start_thread_mutex);
+    thread_join_data[tid].status = (*start_routine)(arg);
+    switch (thread_join_data[tid].state) {
+    case pthreads_st_waited:
+       COND_SIGNAL(&thread_join_data[tid].cond);    
+       break;
+    default:
+       thread_join_data[tid].state = pthreads_st_exited;
+       break;
+    }
+}
+
+int
+pthread_create(perl_os_thread *tid, const pthread_attr_t *attr, 
+              void *(*start_routine)(void*), void *arg)
+{
+    void *args[2];
+
+    args[0] = (void*)start_routine;
+    args[1] = arg;
+
+    MUTEX_LOCK(&start_thread_mutex);
+    *tid = _beginthread(pthread_startit, /*stack*/ NULL, 
+                       /*stacksize*/ 10*1024*1024, (void*)args);
+    MUTEX_LOCK(&start_thread_mutex);
+    MUTEX_UNLOCK(&start_thread_mutex);
+    return *tid ? 0 : EINVAL;
+}
+
+int 
+pthread_detach(perl_os_thread tid)
+{
+    MUTEX_LOCK(&start_thread_mutex);
+    switch (thread_join_data[tid].state) {
+    case pthreads_st_waited:
+       MUTEX_UNLOCK(&start_thread_mutex);
+       croak("detach on a thread with a waiter");
+       break;
+    case pthreads_st_run:
+       thread_join_data[tid].state = pthreads_st_detached;
+       MUTEX_UNLOCK(&start_thread_mutex);
+       break;
+    default:
+       MUTEX_UNLOCK(&start_thread_mutex);
+       croak("detach: unknown thread state: '%s'", 
+             pthreads_states[thread_join_data[tid].state]);
+       break;
+    }
+    return 0;
+}
+
+/* This is a very bastardized version: */
+int
+os2_cond_wait(perl_cond *c, perl_mutex *m)
+{                                              
+    int rc;
+    if ((rc = DosResetEventSem(*c,&na)) && (rc != ERROR_ALREADY_RESET))
+       croak("panic: COND_WAIT-reset: rc=%i", rc);             
+    if (m) MUTEX_UNLOCK(m);                                    
+    if (CheckOSError(DosWaitEventSem(*c,SEM_INDEFINITE_WAIT))
+       && (rc != ERROR_INTERRUPT))
+       croak("panic: COND_WAIT: rc=%i", rc);           
+    if (rc == ERROR_INTERRUPT)
+       errno = EINTR;
+    if (m) MUTEX_LOCK(m);                                      
+} 
+#endif 
+
 /*****************************************************************************/
 /* 2.1 would not resolve symbols on demand, and has no ExtLIBPATH. */
 static PFN ExtFCN[2];                  /* Labeled by ord below. */
@@ -55,7 +209,7 @@ get_sysinfo(ULONG pid, ULONG flags)
     char *pbuffer;
     ULONG rc, buf_len = QSS_INI_BUFFER;
 
-    New(1022, pbuffer, buf_len, char);
+    New(1322, pbuffer, buf_len, char);
     /* QSS_PROCESS | QSS_MODULE | QSS_SEMAPHORES | QSS_SHARED */
     rc = QuerySysState(flags, pid, pbuffer, buf_len);
     while (rc == ERROR_BUFFER_OVERFLOW) {
@@ -196,19 +350,186 @@ result(int flag, int pid)
 #endif
 }
 
+#define EXECF_SPAWN 0
+#define EXECF_EXEC 1
+#define EXECF_TRUEEXEC 2
+#define EXECF_SPAWN_NOWAIT 3
+
+/* Spawn/exec a program, revert to shell if needed. */
+/* global Argv[] contains arguments. */
+
+int
+do_spawn_ve(really, flag, execf)
+SV *really;
+U32 flag;
+U32 execf;
+{
+    dTHR;
+       int trueflag = flag;
+       int rc, secondtry = 0, err;
+       char *tmps;
+       char buf[256], *s = 0;
+       char *args[4];
+       static char * fargs[4] 
+           = { "/bin/sh", "-c", "\"$@\"", "spawn-via-shell", };
+       char **argsp = fargs;
+       char nargs = 4;
+       
+       if (flag == P_WAIT)
+               flag = P_NOWAIT;
+
+      retry:
+       if (strEQ(Argv[0],"/bin/sh")) 
+           Argv[0] = sh_path;
+
+       if (Argv[0][0] != '/' && Argv[0][0] != '\\'
+           && !(Argv[0][0] && Argv[0][1] == ':' 
+                && (Argv[0][2] == '/' || Argv[0][2] != '\\'))
+           ) /* will swawnvp use PATH? */
+           TAINT_ENV();        /* testing IFS here is overkill, probably */
+       /* We should check PERL_SH* and PERLLIB_* as well? */
+       if (!really || !*(tmps = SvPV(really, na)))
+           tmps = Argv[0];
+#if 0
+       rc = result(trueflag, spawnvp(flag,tmps,Argv));
+#else
+       if (execf == EXECF_TRUEEXEC)
+           rc = execvp(tmps,Argv);
+       else if (execf == EXECF_EXEC)
+           rc = spawnvp(trueflag | P_OVERLAY,tmps,Argv);
+       else if (execf == EXECF_SPAWN_NOWAIT)
+           rc = spawnvp(trueflag | P_NOWAIT,tmps,Argv);
+        else                           /* EXECF_SPAWN */
+           rc = result(trueflag, 
+                       spawnvp(trueflag | P_NOWAIT,tmps,Argv));
+#endif 
+       if (rc < 0 && secondtry == 0 
+           && (tmps == Argv[0])) { /* Cannot transfer `really' via shell. */
+           err = errno;
+           if (err == ENOENT) {        /* No such file. */
+               /* One reason may be that EMX added .exe. We suppose
+                  that .exe-less files are automatically shellable.
+                  It might have also been .cmd file without
+                  extension. */
+               char *no_dir;
+               (no_dir = strrchr(Argv[0], '/')) 
+                   || (no_dir = strrchr(Argv[0], '\\'))
+                   || (no_dir = Argv[0]);
+               if (!strchr(no_dir, '.')) {
+                   struct stat buffer;
+                   if (stat(Argv[0], &buffer) != -1) { /* File exists. */
+                       /* Maybe we need to specify the full name here? */
+                       goto doshell;
+                   } else {
+                       /* Try adding script extensions to the file name */
+                       char *scr;
+                       if ((scr = find_script(Argv[0], TRUE, NULL, 0))) {
+                           FILE *file = fopen(scr, "r");
+                           char *s = 0, *s1;
+
+                           Argv[0] = scr;
+                           if (!file)
+                               goto panic_file;
+                           if (!fgets(buf, sizeof buf, file)) {
+                               fclose(file);
+                               goto panic_file;
+                           }
+                           if (fclose(file) != 0) { /* Failure */
+                             panic_file:
+                               warn("Error reading \"%s\": %s", 
+                                    scr, Strerror(errno));
+                               goto doshell;
+                           }
+                           if (buf[0] == '#') {
+                               if (buf[1] == '!')
+                                   s = buf + 2;
+                           } else if (buf[0] == 'e') {
+                               if (strnEQ(buf, "extproc", 7) 
+                                   && isSPACE(buf[7]))
+                                   s = buf + 8;
+                           } else if (buf[0] == 'E') {
+                               if (strnEQ(buf, "EXTPROC", 7)
+                                   && isSPACE(buf[7]))
+                                   s = buf + 8;
+                           }
+                           if (!s)
+                               goto doshell;
+                           s1 = s;
+                           nargs = 0;
+                           argsp = args;
+                           while (1) {
+                               while (isSPACE(*s))
+                                   s++;
+                               if (*s == 0) 
+                                   break;
+                               if (nargs == 4) {
+                                   nargs = -1;
+                                   break;
+                               }
+                               args[nargs++] = s;
+                               while (*s && !isSPACE(*s))
+                                   s++;
+                               if (*s == 0) 
+                                   break;
+                               *s++ = 0;
+                           }
+                           if (nargs == -1) {
+                               warn("Too many args on %.*s line of \"%s\"",
+                                    s1 - buf, buf, scr);
+                               nargs = 4;
+                               argsp = fargs;
+                           }
+                           goto doshell;
+                       }
+                   }
+               }
+               /* Restore errno */
+               errno = err;
+           } else if (err == ENOEXEC) { /* Need to send to shell. */
+             doshell:
+               {
+               char **a = Argv;
+
+               while (a[1])            /* Get to the end */
+                   a++;
+               while (a >= Argv) {
+                   *(a + nargs) = *a;  /* Argv was preallocated to be
+                                          long enough. */
+                   a--;
+               }
+               while (nargs-- >= 0)
+                   Argv[nargs] = argsp[nargs];
+               secondtry = 1;
+               goto retry;
+               }
+           }
+       }
+       if (rc < 0 && dowarn)
+           warn("Can't %s \"%s\": %s\n", 
+                ((execf != EXECF_EXEC && execf != EXECF_TRUEEXEC) 
+                 ? "spawn" : "exec"),
+                Argv[0], Strerror(err));
+       if (rc < 0 && (execf != EXECF_SPAWN_NOWAIT) 
+           && ((trueflag & 0xFF) == P_WAIT)) 
+           rc = 255 << 8; /* Emulate the fork(). */
+
+    return rc;
+}
+
 int
 do_aspawn(really,mark,sp)
 SV *really;
 register SV **mark;
 register SV **sp;
 {
+    dTHR;
     register char **a;
-    char *tmps;
+    char *tmps = NULL;
     int rc;
-    int flag = P_WAIT, trueflag;
+    int flag = P_WAIT, trueflag, err, secondtry = 0;
 
     if (sp > mark) {
-       New(401,Argv, sp - mark + 1, char*);
+       New(1301,Argv, sp - mark + 3, char*);
        a = Argv;
 
        if (mark < sp && SvNIOKp(*(mark+1)) && !SvPOKp(*(mark+1))) {
@@ -224,37 +545,14 @@ register SV **sp;
        }
        *a = Nullch;
 
-       trueflag = flag;
-       if (flag == P_WAIT)
-               flag = P_NOWAIT;
-
-       if (strEQ(Argv[0],"/bin/sh")) Argv[0] = sh_path;
-
-       if (Argv[0][0] != '/' && Argv[0][0] != '\\'
-           && !(Argv[0][0] && Argv[0][1] == ':' 
-                && (Argv[0][2] == '/' || Argv[0][2] != '\\'))
-           ) /* will swawnvp use PATH? */
-           TAINT_ENV();        /* testing IFS here is overkill, probably */
-       /* We should check PERL_SH* and PERLLIB_* as well? */
-       if (really && *(tmps = SvPV(really, na)))
-           rc = result(trueflag, spawnvp(flag,tmps,Argv));
-       else
-           rc = result(trueflag, spawnvp(flag,Argv[0],Argv));
-
-       if (rc < 0 && dowarn)
-           warn("Can't spawn \"%s\": %s", Argv[0], Strerror(errno));
-       if (rc < 0) rc = 255 << 8; /* Emulate the fork(). */
+       rc = do_spawn_ve(really, flag, EXECF_SPAWN);
     } else
        rc = -1;
     do_execfree();
     return rc;
 }
 
-#define EXECF_SPAWN 0
-#define EXECF_EXEC 1
-#define EXECF_TRUEEXEC 2
-#define EXECF_SPAWN_NOWAIT 3
-
+/* Try converting 1-arg form to (usually shell-less) multi-arg form. */
 int
 do_spawn2(cmd, execf)
 char *cmd;
@@ -264,7 +562,8 @@ int execf;
     register char *s;
     char flags[10];
     char *shell, *copt, *news = NULL;
-    int rc;
+    int rc, added_shell = 0, err, seenspace = 0;
+    char fullcmd[MAXNAMLEN + 1];
 
 #ifdef TRYSHELL
     if ((shell = getenv("EMXSHELL")) != NULL)
@@ -290,10 +589,11 @@ int execf;
     if (strnEQ(cmd,"/bin/sh",7) && isSPACE(cmd[7])) {
        STRLEN l = strlen(sh_path);
        
-       New(4545, news, strlen(cmd) - 7 + l, char);
+       New(1302, news, strlen(cmd) - 7 + l + 1, char);
        strcpy(news, sh_path);
        strcpy(news + l, cmd + 7);
        cmd = news;
+       added_shell = 1;
     }
 
     /* save an extra exec if possible */
@@ -314,7 +614,11 @@ int execf;
            if (*s == '\n' && s[1] == '\0') {
                *s = '\0';
                break;
+           } else if (*s == '\\' && !seenspace) {
+               continue;               /* Allow backslashes in names */
            }
+           /* We do not convert this to do_spawn_ve since shell
+              should be smart enough to start itself gloriously. */
          doshell:
            if (execf == EXECF_TRUEEXEC)
                 return execl(shell,shell,copt,cmd,(char*)0);
@@ -332,10 +636,13 @@ int execf;
            if (rc < 0) rc = 255 << 8; /* Emulate the fork(). */
            if (news) Safefree(news);
            return rc;
+       } else if (*s == ' ' || *s == '\t') {
+           seenspace = 1;
        }
     }
 
-    New(402,Argv, (s - cmd) / 2 + 2, char*);
+    /* cmd="a" may lead to "sh", "-c", "\"$@\"", "a", "a.cmd", NULL */
+    New(1303,Argv, (s - cmd + 11) / 2, char*);
     Cmd = savepvn(cmd, s-cmd);
     a = Argv;
     for (s = Cmd; *s;) {
@@ -347,21 +654,9 @@ int execf;
            *s++ = '\0';
     }
     *a = Nullch;
-    if (Argv[0]) {
-       if (execf == EXECF_TRUEEXEC)
-           rc = execvp(Argv[0],Argv);
-       else if (execf == EXECF_EXEC)
-           rc = spawnvp(P_OVERLAY,Argv[0],Argv);
-       else if (execf == EXECF_SPAWN_NOWAIT)
-           rc = spawnvp(P_NOWAIT,Argv[0],Argv);
-        else
-           rc = result(P_WAIT, spawnvp(P_NOWAIT,Argv[0],Argv));
-       if (rc < 0 && dowarn)
-           warn("Can't %s \"%s\": %s", 
-                (execf == EXECF_SPAWN ? "spawn" : "exec"),
-                Argv[0], Strerror(errno));
-       if (rc < 0) rc = 255 << 8; /* Emulate the fork(). */
-    } else
+    if (Argv[0])
+       rc = do_spawn_ve(NULL, 0, execf);
+    else
        rc = -1;
     if (news) Safefree(news);
     do_execfree();
@@ -409,8 +704,6 @@ char        *mode;
     PerlIO *res;
     SV *sv;
     
-    if (pipe(p) < 0)
-       return Nullfp;
     /* `this' is what we use in the parent, `that' in the child. */
     this = (*mode == 'w');
     that = !this;
@@ -418,6 +711,8 @@ char        *mode;
        taint_env();
        taint_proper("Insecure %s%s", "EXEC");
     }
+    if (pipe(p) < 0)
+       return Nullfp;
     /* Now we need to spawn the child. */
     newfd = dup(*mode == 'r');         /* Preserve std* */
     if (p[that] != (*mode == 'r')) {
@@ -432,7 +727,8 @@ char        *mode;
        dup2(newfd, *mode == 'r');      /* Return std* back. */
        close(newfd);
     }
-    close(p[that]);
+    if (p[that] == (*mode == 'r'))
+       close(p[that]);
     if (pid == -1) {
        close(p[this]);
        return NULL;
@@ -670,6 +966,9 @@ mod2fname(sv)
        }
        avlen --;
     }
+#ifdef USE_THREADS
+    sum++;                             /* Avoid conflict of DLLs in memory. */
+#endif 
     fname[pos] = 'A' + (sum % 26);
     fname[pos + 1] = 'A' + (sum / 26 % 26);
     fname[pos + 2] = '\0';
@@ -795,7 +1094,7 @@ XS(XS_Cwd_sys_chdir)
        bool    RETVAL;
 
        RETVAL = sys_chdir(path);
-       ST(0) = RETVAL ? &sv_yes : &sv_no;
+       ST(0) = boolSV(RETVAL);
        if (SvREFCNT(ST(0))) sv_2mortal(ST(0));
     }
     XSRETURN(1);
@@ -811,7 +1110,7 @@ XS(XS_Cwd_change_drive)
        bool    RETVAL;
 
        RETVAL = change_drive(d);
-       ST(0) = RETVAL ? &sv_yes : &sv_no;
+       ST(0) = boolSV(RETVAL);
        if (SvREFCNT(ST(0))) sv_2mortal(ST(0));
     }
     XSRETURN(1);
@@ -827,7 +1126,7 @@ XS(XS_Cwd_sys_is_absolute)
        bool    RETVAL;
 
        RETVAL = sys_is_absolute(path);
-       ST(0) = RETVAL ? &sv_yes : &sv_no;
+       ST(0) = boolSV(RETVAL);
        if (SvREFCNT(ST(0))) sv_2mortal(ST(0));
     }
     XSRETURN(1);
@@ -843,7 +1142,7 @@ XS(XS_Cwd_sys_is_rooted)
        bool    RETVAL;
 
        RETVAL = sys_is_rooted(path);
-       ST(0) = RETVAL ? &sv_yes : &sv_no;
+       ST(0) = boolSV(RETVAL);
        if (SvREFCNT(ST(0))) sv_2mortal(ST(0));
     }
     XSRETURN(1);
@@ -859,7 +1158,7 @@ XS(XS_Cwd_sys_is_relative)
        bool    RETVAL;
 
        RETVAL = sys_is_relative(path);
-       ST(0) = RETVAL ? &sv_yes : &sv_no;
+       ST(0) = boolSV(RETVAL);
        if (SvREFCNT(ST(0))) sv_2mortal(ST(0));
     }
     XSRETURN(1);
@@ -1046,7 +1345,7 @@ XS(XS_Cwd_extLibpath_set)
        }
 
        RETVAL = extLibpath_set(s, type);
-       ST(0) = RETVAL ? &sv_yes : &sv_no;
+       ST(0) = boolSV(RETVAL);
        if (SvREFCNT(ST(0))) sv_2mortal(ST(0));
     }
     XSRETURN(1);
@@ -1084,14 +1383,18 @@ Xs_OS2_init()
 OS2_Perl_data_t OS2_Perl_data;
 
 void
-Perl_OS2_init()
+Perl_OS2_init(char **env)
 {
     char *shell;
 
+    MALLOC_INIT;
     settmppath();
     OS2_Perl_data.xs_init = &Xs_OS2_init;
+    if (environ == NULL) {
+       environ = env;
+    }
     if ( (shell = getenv("PERL_SH_DRIVE")) ) {
-       New(404, sh_path, strlen(SH_PATH) + 1, char);
+       New(1304, sh_path, strlen(SH_PATH) + 1, char);
        strcpy(sh_path, SH_PATH);
        sh_path[0] = shell[0];
     } else if ( (shell = getenv("PERL_SH_DIR")) ) {
@@ -1099,13 +1402,14 @@ Perl_OS2_init()
        if (shell[l-1] == '/' || shell[l-1] == '\\') {
            l--;
        }
-       New(404, sh_path, l + 8, char);
+       New(1304, sh_path, l + 8, char);
        strncpy(sh_path, shell, l);
        strcpy(sh_path + l, "/sh.exe");
        for (i = 0; i < l; i++) {
            if (sh_path[i] == '\\') sh_path[i] = '/';
        }
     }
+    MUTEX_INIT(&start_thread_mutex);
 }
 
 #undef tmpnam
@@ -1138,3 +1442,116 @@ my_tmpfile ()
     return fopen(my_tmpnam(NULL), "w+b"); /* Race condition, but
                                             grants TMP. */
 }
+
+#undef flock
+
+/* This code was contributed by Rocco Caputo. */
+int 
+my_flock(int handle, int o)
+{
+  FILELOCK      rNull, rFull;
+  ULONG         timeout, handle_type, flag_word;
+  APIRET        rc;
+  int           blocking, shared;
+  static int   use_my = -1;
+
+  if (use_my == -1) {
+    char *s = getenv("USE_PERL_FLOCK");
+    if (s)
+       use_my = atoi(s);
+    else 
+       use_my = 1;
+  }
+  if (!(_emx_env & 0x200) || !use_my) 
+    return flock(handle, o);   /* Delegate to EMX. */
+  
+                                        // is this a file?
+  if ((DosQueryHType(handle, &handle_type, &flag_word) != 0) ||
+      (handle_type & 0xFF))
+  {
+    errno = EBADF;
+    return -1;
+  }
+                                        // set lock/unlock ranges
+  rNull.lOffset = rNull.lRange = rFull.lOffset = 0;
+  rFull.lRange = 0x7FFFFFFF;
+                                        // set timeout for blocking
+  timeout = ((blocking = !(o & LOCK_NB))) ? 100 : 1;
+                                        // shared or exclusive?
+  shared = (o & LOCK_SH) ? 1 : 0;
+                                        // do not block the unlock
+  if (o & (LOCK_UN | LOCK_SH | LOCK_EX)) {
+    rc = DosSetFileLocks(handle, &rFull, &rNull, timeout, shared);
+    switch (rc) {
+      case 0:
+        errno = 0;
+        return 0;
+      case ERROR_INVALID_HANDLE:
+        errno = EBADF;
+        return -1;
+      case ERROR_SHARING_BUFFER_EXCEEDED:
+        errno = ENOLCK;
+        return -1;
+      case ERROR_LOCK_VIOLATION:
+        break;                          // not an error
+      case ERROR_INVALID_PARAMETER:
+      case ERROR_ATOMIC_LOCK_NOT_SUPPORTED:
+      case ERROR_READ_LOCKS_NOT_SUPPORTED:
+        errno = EINVAL;
+        return -1;
+      case ERROR_INTERRUPT:
+        errno = EINTR;
+        return -1;
+      default:
+        errno = EINVAL;
+        return -1;
+    }
+  }
+                                        // lock may block
+  if (o & (LOCK_SH | LOCK_EX)) {
+                                        // for blocking operations
+    for (;;) {
+      rc =
+        DosSetFileLocks(
+                handle,
+                &rNull,
+                &rFull,
+                timeout,
+                shared
+        );
+      switch (rc) {
+        case 0:
+          errno = 0;
+          return 0;
+        case ERROR_INVALID_HANDLE:
+          errno = EBADF;
+          return -1;
+        case ERROR_SHARING_BUFFER_EXCEEDED:
+          errno = ENOLCK;
+          return -1;
+        case ERROR_LOCK_VIOLATION:
+          if (!blocking) {
+            errno = EWOULDBLOCK;
+            return -1;
+          }
+          break;
+        case ERROR_INVALID_PARAMETER:
+        case ERROR_ATOMIC_LOCK_NOT_SUPPORTED:
+        case ERROR_READ_LOCKS_NOT_SUPPORTED:
+          errno = EINVAL;
+          return -1;
+        case ERROR_INTERRUPT:
+          errno = EINTR;
+          return -1;
+        default:
+          errno = EINVAL;
+          return -1;
+      }
+                                        // give away timeslice
+      DosSleep(1);
+    }
+  }
+
+  errno = 0;
+  return 0;
+}