implement win32_spawnvp() internally, making it return true PIDs
Gurusamy Sarathy [Mon, 22 Mar 1999 07:07:06 +0000 (07:07 +0000)]
for asynchronous spawns; fix win32_kill() to always deal with
PIDs

p4raw-id: //depot/perl@3123

win32/win32.c
win32/win32.h

index 726c7c5..4d7721e 100644 (file)
@@ -95,7 +95,9 @@ static BOOL           has_shell_metachars(char *ptr);
 static long            filetime_to_clock(PFILETIME ft);
 static BOOL            filetime_from_time(PFILETIME ft, time_t t);
 static char *          get_emd_part(char *leading, char *trailing, ...);
-static void            remove_dead_process(HANDLE deceased);
+static void            remove_dead_process(long deceased);
+static long            find_pid(int pid);
+static char *          qualified_path(const char *cmd);
 
 HANDLE w32_perldll_handle = INVALID_HANDLE_VALUE;
 static DWORD   w32_platform = (DWORD)-1;
@@ -841,42 +843,40 @@ chown(const char *path, uid_t owner, gid_t group)
     return 0;
 }
 
-static void
-remove_dead_process(HANDLE deceased)
+static long
+find_pid(int pid)
 {
-#ifndef USE_RTL_WAIT
-    int child;
+    long child;
     for (child = 0 ; child < w32_num_children ; ++child) {
-       if (w32_child_pids[child] == deceased) {
-           Copy(&w32_child_pids[child+1], &w32_child_pids[child],
-                (w32_num_children-child-1), HANDLE);
-           w32_num_children--;
-           break;
-       }
+       if (w32_child_pids[child] == pid)
+           return child;
+    }
+    return -1;
+}
+
+static void
+remove_dead_process(long child)
+{
+    if (child >= 0) {
+       CloseHandle(w32_child_handles[child]);
+       Copy(&w32_child_handles[child+1], &w32_child_handles[child],
+            (w32_num_children-child-1), HANDLE);
+       Copy(&w32_child_pids[child+1], &w32_child_pids[child],
+            (w32_num_children-child-1), DWORD);
+       w32_num_children--;
     }
-#endif
 }
 
 DllExport int
 win32_kill(int pid, int sig)
 {
-#ifdef USE_RTL_WAIT
-    HANDLE hProcess= OpenProcess(PROCESS_ALL_ACCESS, TRUE, pid);
-#else
-    HANDLE hProcess = (HANDLE) pid;
-#endif
-
-    if (hProcess == NULL) {
-       croak("kill process failed!\n");
-    }
-    else {
-       if (!TerminateProcess(hProcess, sig))
-           croak("kill process failed!\n");
+    HANDLE hProcess;
+    hProcess = OpenProcess(PROCESS_ALL_ACCESS, TRUE, pid);
+    if (hProcess && TerminateProcess(hProcess, sig))
        CloseHandle(hProcess);
-
-       /* WaitForMultipleObjects() on a pid that was killed returns error
-        * so if we know the pid is gone we remove it from process list */
-       remove_dead_process(hProcess);
+    else {
+       errno = EINVAL;
+       return -1;
     }
     return 0;
 }
@@ -1135,27 +1135,40 @@ win32_utime(const char *filename, struct utimbuf *times)
 DllExport int
 win32_waitpid(int pid, int *status, int flags)
 {
-    int rc;
+    int retval = -1;
     if (pid == -1) 
-      return win32_wait(status);
+       return win32_wait(status);
     else {
-      rc = cwait(status, pid, WAIT_CHILD);
-    /* cwait() returns "correctly" on Borland */
+       long child = find_pid(pid);
+       if (child >= 0) {
+           HANDLE hProcess = w32_child_handles[child];
+           DWORD waitcode = WaitForSingleObject(hProcess, INFINITE);
+           if (waitcode != WAIT_FAILED) {
+               if (GetExitCodeProcess(hProcess, &waitcode)) {
+                   *status = (int)((waitcode & 0xff) << 8);
+                   retval = (int)w32_child_pids[child];
+                   remove_dead_process(child);
+                   return retval;
+               }
+           }
+           else
+               errno = ECHILD;
+       }
+       else {
+           retval = cwait(status, pid, WAIT_CHILD);
+           /* cwait() returns "correctly" on Borland */
 #ifndef __BORLANDC__
-    if (status)
-       *status *= 256;
+           if (status)
+               *status *= 256;
 #endif
-      remove_dead_process((HANDLE)pid);
+       }
     }
-    return rc >= 0 ? pid : rc;                
+    return retval >= 0 ? pid : retval;                
 }
 
 DllExport int
 win32_wait(int *status)
 {
-#ifdef USE_RTL_WAIT
-    return wait(status);
-#else
     /* XXX this wait emulation only knows about processes
      * spawned via win32_spawnvp(P_NOWAIT, ...).
      */
@@ -1169,7 +1182,7 @@ win32_wait(int *status)
 
     /* if a child exists, wait for it to die */
     waitcode = WaitForMultipleObjects(w32_num_children,
-                                     w32_child_pids,
+                                     w32_child_handles,
                                      FALSE,
                                      INFINITE);
     if (waitcode != WAIT_FAILED) {
@@ -1178,13 +1191,10 @@ win32_wait(int *status)
            i = waitcode - WAIT_ABANDONED_0;
        else
            i = waitcode - WAIT_OBJECT_0;
-       if (GetExitCodeProcess(w32_child_pids[i], &exitcode) ) {
-           CloseHandle(w32_child_pids[i]);
+       if (GetExitCodeProcess(w32_child_handles[i], &exitcode) ) {
            *status = (int)((exitcode & 0xff) << 8);
            retval = (int)w32_child_pids[i];
-           Copy(&w32_child_pids[i+1], &w32_child_pids[i],
-                (w32_num_children-i-1), HANDLE);
-           w32_num_children--;
+           remove_dead_process(i);
            return retval;
        }
     }
@@ -1192,8 +1202,6 @@ win32_wait(int *status)
 FAILED:
     errno = GetLastError();
     return -1;
-
-#endif
 }
 
 static UINT timerid = 0;
@@ -1791,16 +1799,10 @@ win32_pclose(FILE *pf)
     win32_fclose(pf);
     SvIVX(sv) = 0;
 
-    remove_dead_process((HANDLE)childpid);
+    if (win32_waitpid(childpid, &status, 0) == -1)
+        return -1;
 
-    /* wait for the child */
-    if (cwait(&status, childpid, WAIT_CHILD) == -1)
-        return (-1);
-    /* cwait() returns "correctly" on Borland */
-#ifndef __BORLANDC__
-    status *= 256;
-#endif
-    return (status);
+    return status;
 
 #endif /* USE_RTL_POPEN */
 }
@@ -1993,26 +1995,212 @@ win32_chdir(const char *dir)
     return chdir(dir);
 }
 
+static char *
+create_command_line(const char* command, const char * const *args)
+{
+    int index;
+    char *cmd, *ptr, *arg;
+    STRLEN len = strlen(command) + 1;
+
+    for (index = 0; (ptr = (char*)args[index]) != NULL; ++index)
+       len += strlen(ptr) + 1;
+
+    New(1310, cmd, len, char);
+    ptr = cmd;
+    strcpy(ptr, command);
+    ptr += strlen(ptr);
+    *ptr++ = ' ';
+
+    for (index = 0; (arg = (char*)args[index]) != NULL; ++index) {
+       strcpy(ptr, arg);
+       ptr += strlen(ptr);
+       if ((char*)args[index+1] != NULL)
+           *ptr++ = ' ';
+    }
+
+    return cmd;
+}
+
+static char *
+qualified_path(const char *cmd)
+{
+    char *pathstr;
+    char *fullcmd, *curfullcmd;
+    STRLEN cmdlen = 0;
+    int has_slash = 0;
+
+    if (!cmd)
+       return Nullch;
+    fullcmd = (char*)cmd;
+    while (*fullcmd) {
+       if (*fullcmd == '/' || *fullcmd == '\\')
+           has_slash++;
+       fullcmd++;
+       cmdlen++;
+    }
+
+    /* look in PATH */
+    pathstr = win32_getenv("PATH");
+    New(0, fullcmd, MAX_PATH+1, char);
+    curfullcmd = fullcmd;
+
+    while (1) {
+       DWORD res;
+
+       /* start by appending the name to the current prefix */
+       strcpy(curfullcmd, cmd);
+       curfullcmd += cmdlen;
+
+       /* if it doesn't end with '.', or has no extension, try adding
+        * a trailing .exe first */
+       if (cmd[cmdlen-1] != '.'
+           && (cmdlen < 4 || cmd[cmdlen-4] != '.'))
+       {
+           strcpy(curfullcmd, ".exe");
+           res = GetFileAttributes(fullcmd);
+           if (res != 0xFFFFFFFF && !(res & FILE_ATTRIBUTE_DIRECTORY))
+               return fullcmd;
+           *curfullcmd = '\0';
+       }
+
+       /* that failed, try the bare name */
+       res = GetFileAttributes(fullcmd);
+       if (res != 0xFFFFFFFF && !(res & FILE_ATTRIBUTE_DIRECTORY))
+           return fullcmd;
+
+       /* quit if no other path exists, or if cmd already has path */
+       if (!pathstr || !*pathstr || has_slash)
+           break;
+
+       /* skip leading semis */
+       while (*pathstr == ';')
+           pathstr++;
+
+       /* build a new prefix from scratch */
+       curfullcmd = fullcmd;
+       while (*pathstr && *pathstr != ';') {
+           if (*pathstr == '"') {      /* foo;"baz;etc";bar */
+               pathstr++;              /* skip initial '"' */
+               while (*pathstr && *pathstr != '"') {
+                   if (curfullcmd-fullcmd < MAX_PATH-cmdlen-5)
+                       *curfullcmd++ = *pathstr;
+                   pathstr++;
+               }
+               if (*pathstr)
+                   pathstr++;          /* skip trailing '"' */
+           }
+           else {
+               if (curfullcmd-fullcmd < MAX_PATH-cmdlen-5)
+                   *curfullcmd++ = *pathstr;
+               pathstr++;
+           }
+       }
+       if (*pathstr)
+           pathstr++;                  /* skip trailing semi */
+       if (curfullcmd > fullcmd        /* append a dir separator */
+           && curfullcmd[-1] != '/' && curfullcmd[-1] != '\\')
+       {
+           *curfullcmd++ = '\\';
+       }
+    }
+GIVE_UP:
+    Safefree(fullcmd);
+    return Nullch;
+}
+
+/* XXX this needs to be made more compatible with the spawnvp()
+ * provided by the various RTLs.  In particular, searching for
+ * *.{com,bat,cmd} files (as done by the RTLs) is unimplemented.
+ * This doesn't significantly affect perl itself, because we
+ * always invoke things using PERL5SHELL if a direct attempt to
+ * spawn the executable fails.
+ * 
+ * XXX splitting and rejoining the commandline between do_aspawn()
+ * and win32_spawnvp() could also be avoided.
+ */
+
 DllExport int
 win32_spawnvp(int mode, const char *cmdname, const char *const *argv)
 {
-    int status;
+#ifdef USE_RTL_SPAWNVP
+    return spawnvp(mode, cmdname, (char * const *)argv);
+#else
+    DWORD ret;
+    STARTUPINFO StartupInfo;
+    PROCESS_INFORMATION ProcessInformation;
+    DWORD create = 0;
+
+    char *cmd = create_command_line(cmdname, strcmp(cmdname, argv[0]) == 0
+                                            ? &argv[1] : argv);
+    char *fullcmd = Nullch;
+
+    switch(mode) {
+    case P_NOWAIT:     /* asynch + remember result */
+       if (w32_num_children >= MAXIMUM_WAIT_OBJECTS) {
+           errno = EAGAIN;
+           ret = -1;
+           goto RETVAL;
+       }
+       /* FALL THROUGH */
+    case P_WAIT:       /* synchronous execution */
+       break;
+    default:           /* invalid mode */
+       errno = EINVAL;
+       ret = -1;
+       goto RETVAL;
+    }
+    memset(&StartupInfo,0,sizeof(StartupInfo));
+    StartupInfo.cb = sizeof(StartupInfo);
+    StartupInfo.wShowWindow = SW_SHOWDEFAULT;
+
+RETRY:
+    if (!CreateProcess(cmdname,                /* search PATH to find executable */
+                      cmd,             /* executable, and its arguments */
+                      NULL,            /* process attributes */
+                      NULL,            /* thread attributes */
+                      TRUE,            /* inherit handles */
+                      create,          /* creation flags */
+                      NULL,            /* inherit environment */
+                      NULL,            /* inherit cwd */
+                      &StartupInfo,
+                      &ProcessInformation))
+    {
+       /* initial NULL argument to CreateProcess() does a PATH
+        * search, but it always first looks in the directory
+        * where the current process was started, which behavior
+        * is undesirable for backward compatibility.  So we
+        * jump through our own hoops by picking out the path
+        * we really want it to use. */
+       if (!fullcmd) {
+           fullcmd = qualified_path(cmdname);
+           if (fullcmd) {
+               cmdname = fullcmd;
+               goto RETRY;
+           }
+       }
+       errno = ENOENT;
+       ret = -1;
+       goto RETVAL;
+    }
 
-#ifndef USE_RTL_WAIT
-    if (mode == P_NOWAIT && w32_num_children >= MAXIMUM_WAIT_OBJECTS)
-       return -1;
-#endif
+    if (mode == P_NOWAIT) {
+       /* asynchronous spawn -- store handle, return PID */
+       w32_child_handles[w32_num_children] = ProcessInformation.hProcess;
+       ret = w32_child_pids[w32_num_children] = ProcessInformation.dwProcessId;
+       ++w32_num_children;
+    }
+    else  {
+       WaitForSingleObject(ProcessInformation.hProcess, INFINITE);
+       GetExitCodeProcess(ProcessInformation.hProcess, &ret);
+       CloseHandle(ProcessInformation.hProcess);
+    }
 
-    status = spawnvp(mode, cmdname, (char * const *) argv);
-#ifndef USE_RTL_WAIT
-    /* XXX For the P_NOWAIT case, Borland RTL returns pinfo.dwProcessId
-     * while VC RTL returns pinfo.hProcess. For purposes of the custom
-     * implementation of win32_wait(), we assume the latter.
-     */
-    if (mode == P_NOWAIT && status >= 0)
-       w32_child_pids[w32_num_children++] = (HANDLE)status;
+    CloseHandle(ProcessInformation.hThread);
+RETVAL:
+    Safefree(cmd);
+    Safefree(fullcmd);
+    return (int)ret;
 #endif
-    return status;
 }
 
 DllExport int
@@ -2567,9 +2755,8 @@ Perl_init_os_extras()
     w32_perlshell_tokens = Nullch;
     w32_perlshell_items = -1;
     w32_fdpid = newAV();               /* XXX needs to be in Perl_win32_init()? */
-#ifndef USE_RTL_WAIT
+    New(1313, w32_children, 1, child_tab);
     w32_num_children = 0;
-#endif
 
     /* these names are Activeware compatible */
     newXS("Win32::GetCwd", w32_GetCwd, file);
index fef3cbc..0b8b710 100644 (file)
@@ -161,8 +161,6 @@ struct tms {
 #pragma warn -pro      /* "call to function with no prototype" */
 #pragma warn -stu      /* "undefined structure 'foo'" */
 
-#define USE_RTL_WAIT   /* Borland has a working wait() */
-
 /* Borland is picky about a bare member function name used as its ptr */
 #ifdef PERL_OBJECT
 #define FUNC_NAME_TO_PTR(name) &(name)
@@ -329,26 +327,29 @@ EXT void win32_strip_return(struct sv *sv);
 #endif
 
 #define HAVE_INTERP_INTERN
+typedef struct {
+    long       num;
+    DWORD      pids[MAXIMUM_WAIT_OBJECTS];
+} child_tab;
+
 struct interp_intern {
-    char *     w32_perlshell_tokens;
-    char **    w32_perlshell_vec;
-    long       w32_perlshell_items;
-    struct av *        w32_fdpid;
-#ifndef USE_RTL_WAIT
-    long       w32_num_children;
-    HANDLE     w32_child_pids[MAXIMUM_WAIT_OBJECTS];
-#endif
+    char *     perlshell_tokens;
+    char **    perlshell_vec;
+    long       perlshell_items;
+    struct av *        fdpid;
+    child_tab *        children;
+    HANDLE     child_handles[MAXIMUM_WAIT_OBJECTS];
 };
 
-#define w32_perlshell_tokens   (PL_sys_intern.w32_perlshell_tokens)
-#define w32_perlshell_vec      (PL_sys_intern.w32_perlshell_vec)
-#define w32_perlshell_items    (PL_sys_intern.w32_perlshell_items)
-#define w32_fdpid              (PL_sys_intern.w32_fdpid)
 
-#ifndef USE_RTL_WAIT
-#  define w32_num_children     (PL_sys_intern.w32_num_children)
-#  define w32_child_pids       (PL_sys_intern.w32_child_pids)
-#endif
+#define w32_perlshell_tokens   (PL_sys_intern.perlshell_tokens)
+#define w32_perlshell_vec      (PL_sys_intern.perlshell_vec)
+#define w32_perlshell_items    (PL_sys_intern.perlshell_items)
+#define w32_fdpid              (PL_sys_intern.fdpid)
+#define w32_children           (PL_sys_intern.children)
+#define w32_num_children       (w32_children->num)
+#define w32_child_pids         (w32_children->pids)
+#define w32_child_handles      (PL_sys_intern.child_handles)
 
 /* 
  * Now Win32 specific per-thread data stuff