tidy-up: process.h detection and use

This patch aims to cleanup the use of `process.h` header and the macro
`HAVE_PROCESS_H` associated with it.

- `process.h` is always available on Windows. In curl, it is required
  only for `_beginthreadex()` in `lib/curl_threads.c`.

- `process.h` is also available in MS-DOS. In curl, its only use was in
  `lib/smb.c` for `getpid()`. But `getpid()` is in fact declared by
  `unistd.h`, which is always enabled via `lib/config-dos.h`. So the
  header is not necessary.

- `HAVE_PROCESS_H` was detected by CMake, forced to 1 on Windows and
  left to real detection for other platforms.
  It was also set to always-on in `lib/config-win32.h` and
  `lib/config-dos.h`.
  In autotools builds, there was no detection and the macro was never
  set.

Based on these observations, in this patch we:

- Rework Windows `getpid` logic in `lib/smb.c` to always use the
  equivalent direct Win32 API function `GetCurrentProcessId()`, as we
  already did for Windows UWP apps. This makes `process.h` unnecessary
  here on Windows.

- Stop #including `process.h` into files where it was not necessary.
  This is everywhere, except `lib/curl_threads.c`.

  > Strangely enough, `lib/curl_threads.c` compiled fine with autotools
  > because `process.h` is also indirecty included via `unistd.h`. This
  > might have been broken in autotools MSVC builds, where the latter
  > header is missing.

- Delete all remaining `HAVE_PROCESS_H` feature guards, for they were
  unnecessary.

- Delete `HAVE_PROCESS_H` detection from CMake and predefined values
  from `lib/config-*.h` headers.

Reviewed-by: Jay Satiro
Closes #9703

CMake/Platforms/WindowsCache.cmake

@@ -34,7 +34,6 @@ if(NOT UNIX)
     set(HAVE_NETDB_H 0)
     set(HAVE_NETINET_IN_H 0)
     set(HAVE_NET_IF_H 0)
-    set(HAVE_PROCESS_H 1)
     set(HAVE_PWD_H 0)
     set(HAVE_SETJMP_H 1)
     set(HAVE_SIGNAL_H 1)

CMakeLists.txt

@@ -1006,7 +1006,6 @@ check_include_file_concat("time.h"           HAVE_TIME_H)
 check_include_file_concat("unistd.h"         HAVE_UNISTD_H)
 check_include_file_concat("utime.h"          HAVE_UTIME_H)
 
-check_include_file_concat("process.h"        HAVE_PROCESS_H)
 check_include_file_concat("stddef.h"         HAVE_STDDEF_H)
 check_include_file_concat("stdint.h"        HAVE_STDINT_H)
 check_include_file_concat("sys/utsname.h"   HAVE_SYS_UTSNAME_H)

lib/asyn-ares.c

@@ -47,10 +47,6 @@
 #include <inet.h>
 #endif
 
-#ifdef HAVE_PROCESS_H
-#include <process.h>
-#endif
-
 #if (defined(NETWARE) && defined(__NOVELL_LIBC__))
 #undef in_addr_t
 #define in_addr_t unsigned long

lib/asyn-thread.c

@@ -44,14 +44,8 @@
 #include <inet.h>
 #endif
 
-#if defined(USE_THREADS_POSIX)
-#  ifdef HAVE_PTHREAD_H
-#    include <pthread.h>
-#  endif
-#elif defined(USE_THREADS_WIN32)
-#  ifdef HAVE_PROCESS_H
-#    include <process.h>
-#  endif
+#if defined(USE_THREADS_POSIX) && defined(HAVE_PTHREAD_H)
+#  include <pthread.h>
 #endif
 
 #if (defined(NETWARE) && defined(__NOVELL_LIBC__))

lib/config-dos.h

@@ -56,7 +56,6 @@
 #define HAVE_NETINET_IN_H      1
 #define HAVE_NETINET_TCP_H     1
 #define HAVE_NET_IF_H          1
-#define HAVE_PROCESS_H         1
 #define HAVE_RECV              1
 #define HAVE_SELECT            1
 #define HAVE_SEND              1

lib/config-win32.h

@@ -66,11 +66,6 @@
 /* Define if you have the <netinet/in.h> header file. */
 /* #define HAVE_NETINET_IN_H 1 */
 
-/* Define if you have the <process.h> header file. */
-#ifndef __SALFORDC__
-#define HAVE_PROCESS_H 1
-#endif
-
 /* Define if you have the <signal.h> header file. */
 #define HAVE_SIGNAL_H 1
 

lib/config-win32ce.h

@@ -65,9 +65,6 @@
 /* Define if you have the <stdlib.h> header file.  */
 #define HAVE_STDLIB_H 1
 
-/* Define if you have the <process.h> header file.  */
-/* #define HAVE_PROCESS_H 1 */
-
 /* Define if you have the <sys/param.h> header file.  */
 /* #define HAVE_SYS_PARAM_H 1 */
 

lib/curl_config.h.cmake

@@ -595,9 +595,6 @@
 /* Define to 1 if you have the ws2tcpip.h header file. */
 #cmakedefine HAVE_WS2TCPIP_H 1
 
-/* Define if you have the <process.h> header file. */
-#cmakedefine HAVE_PROCESS_H 1
-
 /* Define to 1 if you need the lber.h header file even with ldap.h */
 #cmakedefine NEED_LBER_H 1
 

lib/curl_threads.c

@@ -31,9 +31,7 @@
 #    include <pthread.h>
 #  endif
 #elif defined(USE_THREADS_WIN32)
-#  ifdef HAVE_PROCESS_H
-#    include <process.h>
-#  endif
+#  include <process.h>
 #endif
 
 #include "curl_threads.h"

lib/hostasyn.c

@@ -43,10 +43,6 @@
 #include <inet.h>
 #endif
 
-#ifdef HAVE_PROCESS_H
-#include <process.h>
-#endif
-
 #include "urldata.h"
 #include "sendf.h"
 #include "hostip.h"

lib/hostip.c

@@ -48,10 +48,6 @@
 #include <signal.h>
 #endif
 
-#ifdef HAVE_PROCESS_H
-#include <process.h>
-#endif
-
 #include "urldata.h"
 #include "sendf.h"
 #include "hostip.h"

lib/hostip4.c

@@ -43,10 +43,6 @@
 #include <inet.h>
 #endif
 
-#ifdef HAVE_PROCESS_H
-#include <process.h>
-#endif
-
 #include "urldata.h"
 #include "sendf.h"
 #include "hostip.h"

lib/hostip6.c

@@ -43,10 +43,6 @@
 #include <inet.h>
 #endif
 
-#ifdef HAVE_PROCESS_H
-#include <process.h>
-#endif
-
 #include "urldata.h"
 #include "sendf.h"
 #include "hostip.h"

lib/hostsyn.c

@@ -43,10 +43,6 @@
 #include <inet.h>
 #endif
 
-#ifdef HAVE_PROCESS_H
-#include <process.h>
-#endif
-
 #include "urldata.h"
 #include "sendf.h"
 #include "hostip.h"

lib/smb.c

@@ -30,13 +30,8 @@
 
 #define BUILDING_CURL_SMB_C
 
-#ifdef HAVE_PROCESS_H
-#include <process.h>
-#ifdef CURL_WINDOWS_APP
+#ifdef WIN32
 #define getpid GetCurrentProcessId
-#elif defined(WIN32)
-#define getpid _getpid
-#endif
 #endif
 
 #include "smb.h"

lib/vtls/mbedtls_threadlock.c

@@ -26,13 +26,12 @@
 
 #if defined(USE_MBEDTLS) &&                                     \
   ((defined(USE_THREADS_POSIX) && defined(HAVE_PTHREAD_H)) ||   \
-   (defined(USE_THREADS_WIN32) && defined(HAVE_PROCESS_H)))
+    defined(USE_THREADS_WIN32))
 
 #if defined(USE_THREADS_POSIX) && defined(HAVE_PTHREAD_H)
 #  include <pthread.h>
 #  define MBEDTLS_MUTEX_T pthread_mutex_t
-#elif defined(USE_THREADS_WIN32) && defined(HAVE_PROCESS_H)
-#  include <process.h>
+#elif defined(USE_THREADS_WIN32)
 #  define MBEDTLS_MUTEX_T HANDLE
 #endif
 
@@ -60,7 +59,7 @@ int Curl_mbedtlsthreadlock_thread_setup(void)
 #if defined(USE_THREADS_POSIX) && defined(HAVE_PTHREAD_H)
     if(pthread_mutex_init(&mutex_buf[i], NULL))
       return 0; /* pthread_mutex_init failed */
-#elif defined(USE_THREADS_WIN32) && defined(HAVE_PROCESS_H)
+#elif defined(USE_THREADS_WIN32)
     mutex_buf[i] = CreateMutex(0, FALSE, 0);
     if(mutex_buf[i] == 0)
       return 0;  /* CreateMutex failed */
@@ -81,7 +80,7 @@ int Curl_mbedtlsthreadlock_thread_cleanup(void)
 #if defined(USE_THREADS_POSIX) && defined(HAVE_PTHREAD_H)
     if(pthread_mutex_destroy(&mutex_buf[i]))
       return 0; /* pthread_mutex_destroy failed */
-#elif defined(USE_THREADS_WIN32) && defined(HAVE_PROCESS_H)
+#elif defined(USE_THREADS_WIN32)
     if(!CloseHandle(mutex_buf[i]))
       return 0; /* CloseHandle failed */
 #endif /* USE_THREADS_POSIX && HAVE_PTHREAD_H */
@@ -101,7 +100,7 @@ int Curl_mbedtlsthreadlock_lock_function(int n)
                      "Error: mbedtlsthreadlock_lock_function failed\n"));
       return 0; /* pthread_mutex_lock failed */
     }
-#elif defined(USE_THREADS_WIN32) && defined(HAVE_PROCESS_H)
+#elif defined(USE_THREADS_WIN32)
     if(WaitForSingleObject(mutex_buf[n], INFINITE) == WAIT_FAILED) {
       DEBUGF(fprintf(stderr,
                      "Error: mbedtlsthreadlock_lock_function failed\n"));
@@ -121,7 +120,7 @@ int Curl_mbedtlsthreadlock_unlock_function(int n)
                      "Error: mbedtlsthreadlock_unlock_function failed\n"));
       return 0; /* pthread_mutex_unlock failed */
     }
-#elif defined(USE_THREADS_WIN32) && defined(HAVE_PROCESS_H)
+#elif defined(USE_THREADS_WIN32)
     if(!ReleaseMutex(mutex_buf[n])) {
       DEBUGF(fprintf(stderr,
                      "Error: mbedtlsthreadlock_unlock_function failed\n"));

lib/vtls/mbedtls_threadlock.h

@@ -29,7 +29,7 @@
 #ifdef USE_MBEDTLS
 
 #if (defined(USE_THREADS_POSIX) && defined(HAVE_PTHREAD_H)) || \
-    (defined(USE_THREADS_WIN32) && defined(HAVE_PROCESS_H))
+     defined(USE_THREADS_WIN32)
 
 int Curl_mbedtlsthreadlock_thread_setup(void);
 int Curl_mbedtlsthreadlock_thread_cleanup(void);