ps: add support for CPU and elapsed time columns

It may be necessary to run ps as administrator to get information
about processes belonging to other users.

The code to detect GetTickCount64 at run-time was imported from
Git for Windows.

3 files changed, 106 insertions, 2 deletions

diff --git a/win32/lazyload.h b/win32/lazyload.h
new file mode 100644
index 000000000..9d1a05550
--- /dev/null
+++ b/win32/lazyload.h
@@ -0,0 +1,43 @@
+#ifndef LAZYLOAD_H
+#define LAZYLOAD_H
+
+/* simplify loading of DLL functions */
+
+struct proc_addr {
+        const char *const dll;
+        const char *const function;
+        FARPROC pfunction;
+        unsigned initialized : 1;
+};
+
+/* Declares a function to be loaded dynamically from a DLL. */
+#define DECLARE_PROC_ADDR(dll, rettype, function, ...) \
+        static struct proc_addr proc_addr_##function = \
+        { #dll, #function, NULL, 0 }; \
+        static rettype (WINAPI *function)(__VA_ARGS__)
+
+/*
+ * Loads a function from a DLL (once-only).
+ * Returns non-NULL function pointer on success.
+ * Returns NULL + errno == ENOSYS on failure.
+ */
+#define INIT_PROC_ADDR(function) (function = get_proc_addr(&proc_addr_##function))
+
+static inline void *get_proc_addr(struct proc_addr *proc)
+{
+        /* only do this once */
+        if (!proc->initialized) {
+                HANDLE hnd;
+                proc->initialized = 1;
+                hnd = LoadLibraryExA(proc->dll, NULL,
+                                     LOAD_LIBRARY_SEARCH_SYSTEM32);
+                if (hnd)
+                        proc->pfunction = GetProcAddress(hnd, proc->function);
+        }
+        /* set ENOSYS if DLL or function was not found */
+        if (!proc->pfunction)
+                errno = ENOSYS;
+        return proc->pfunction;
+}
+
+#endif
diff --git a/win32/mingw.c b/win32/mingw.c
index 7f37eadda..afcb6c6d2 100644
--- a/win32/mingw.c
+++ b/win32/mingw.c
@@ -707,7 +707,7 @@ int getlogin_r(char *buf, size_t len)
 long sysconf(int name)
 {
         if ( name == _SC_CLK_TCK ) {
-                return 100;
+                return TICKS_PER_SECOND;
         }
         errno = EINVAL;
         return -1;
@@ -1064,3 +1064,19 @@ off_t mingw_lseek(int fd, off_t offset, int whence)
         }
         return _lseeki64(fd, offset, whence);
 }
+
+#if ENABLE_FEATURE_PS_TIME || ENABLE_FEATURE_PS_LONG
+#undef GetTickCount64
+#include "lazyload.h"
+
+ULONGLONG CompatGetTickCount64(void)
+{
+        DECLARE_PROC_ADDR(kernel32.dll, ULONGLONG, GetTickCount64, void);
+
+        if (!INIT_PROC_ADDR(GetTickCount64)) {
+                return (ULONGLONG)GetTickCount();
+        }
+
+        return GetTickCount64();
+}
+#endif
diff --git a/win32/process.c b/win32/process.c
index c0ff78105..f88a4898c 100644
--- a/win32/process.c
+++ b/win32/process.c
@@ -334,8 +334,18 @@ mingw_execv(const char *cmd, char *const *argv)
         return mingw_execve(cmd, argv, environ);
 }
 
+static inline long long filetime_to_ticks(const FILETIME *ft)
+{
+        return (((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime)/
+                                HNSEC_PER_TICK;
+}
+
 /* POSIX version in libbb/procps.c */
-procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags UNUSED_PARAM)
+procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags
+#if !ENABLE_FEATURE_PS_TIME && !ENABLE_FEATURE_PS_LONG
+UNUSED_PARAM
+#endif
+)
 {
         PROCESSENTRY32 pe;
 
@@ -361,6 +371,41 @@ procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags UNUSED_PAR
                 }
         }
 
+#if ENABLE_FEATURE_PS_TIME || ENABLE_FEATURE_PS_LONG
+        if (flags & (PSSCAN_STIME|PSSCAN_UTIME|PSSCAN_START_TIME)) {
+                HANDLE proc;
+                FILETIME crTime, exTime, keTime, usTime;
+
+                if ((proc=OpenProcess(PROCESS_QUERY_LIMITED_INFORMATION,
+                                        FALSE, pe.th32ProcessID))) {
+                        if (GetProcessTimes(proc, &crTime, &exTime, &keTime, &usTime)) {
+                                /* times in ticks since 1 January 1601 */
+                                static long long boot_time = 0;
+                                long long start_time;
+
+                                if (boot_time == 0) {
+                                        long long ticks_since_boot;
+                                        FILETIME now;
+
+                                        ticks_since_boot = GetTickCount64()/MS_PER_TICK;
+                                        GetSystemTimeAsFileTime(&now);
+                                        boot_time = filetime_to_ticks(&now) - ticks_since_boot;
+                                }
+
+                                start_time = filetime_to_ticks(&crTime);
+                                sp->start_time = (unsigned long)(start_time - boot_time);
+
+                                sp->stime = (unsigned long)filetime_to_ticks(&keTime);
+                                sp->utime = (unsigned long)filetime_to_ticks(&usTime);
+                        }
+                        else {
+                                sp->start_time = sp->stime = sp->utime = 0;
+                        }
+                        CloseHandle(proc);
+                }
+        }
+#endif
+
         sp->pid = pe.th32ProcessID;
         sp->ppid = pe.th32ParentProcessID;
         safe_strncpy(sp->comm, pe.szExeFile, COMM_LEN);