style fix, no code changes
[oweals/busybox.git] / procps / ps.c
index 3a5af7c18691b79a6a776563f5f78cafa98a999f..815c11578ae1ed6d4f3c16b56f6fd25ff841ae46 100644 (file)
@@ -8,6 +8,54 @@
  *
  * Licensed under GPLv2, see file LICENSE in this source tree.
  */
+//config:config PS
+//config:      bool "ps (11 kb)"
+//config:      default y
+//config:      help
+//config:      ps gives a snapshot of the current processes.
+//config:
+//config:config FEATURE_PS_WIDE
+//config:      bool "Enable wide output (-w)"
+//config:      default y
+//config:      depends on (PS || MINIPS) && !DESKTOP
+//config:      help
+//config:      Support argument 'w' for wide output.
+//config:      If given once, 132 chars are printed, and if given more
+//config:      than once, the length is unlimited.
+//config:
+//config:config FEATURE_PS_LONG
+//config:      bool "Enable long output (-l)"
+//config:      default y
+//config:      depends on (PS || MINIPS) && !DESKTOP
+//config:      help
+//config:      Support argument 'l' for long output.
+//config:      Adds fields PPID, RSS, START, TIME & TTY
+//config:
+//config:config FEATURE_PS_TIME
+//config:      bool "Enable -o time and -o etime specifiers"
+//config:      default y
+//config:      depends on (PS || MINIPS) && DESKTOP
+//config:      select PLATFORM_LINUX
+//config:
+//config:config FEATURE_PS_UNUSUAL_SYSTEMS
+//config:      bool "Support Linux prior to 2.4.0 and non-ELF systems"
+//config:      default n
+//config:      depends on FEATURE_PS_TIME
+//config:      help
+//config:      Include support for measuring HZ on old kernels and non-ELF systems
+//config:      (if you are on Linux 2.4.0+ and use ELF, you don't need this)
+//config:
+//config:config FEATURE_PS_ADDITIONAL_COLUMNS
+//config:      bool "Enable -o rgroup, -o ruser, -o nice specifiers"
+//config:      default y
+//config:      depends on (PS || MINIPS) && DESKTOP
+
+//                 APPLET_NOEXEC:name    main location    suid_type     help
+//applet:IF_PS(    APPLET_NOEXEC(ps,     ps,  BB_DIR_BIN, BB_SUID_DROP, ps))
+//applet:IF_MINIPS(APPLET_NOEXEC(minips, ps,  BB_DIR_BIN, BB_SUID_DROP, ps))
+
+//kbuild:lib-$(CONFIG_PS) += ps.o
+//kbuild:lib-$(CONFIG_MINIPS) += ps.o
 
 //usage:#if ENABLE_DESKTOP
 //usage:
 //usage:       " 2990 andersen andersen R ps\n"
 
 #include "libbb.h"
+#include "common_bufsiz.h"
 #ifdef __linux__
 # include <sys/sysinfo.h>
 #endif
 enum { MAX_WIDTH = 2*1024 };
 
 #if ENABLE_FEATURE_PS_TIME || ENABLE_FEATURE_PS_LONG
-static long get_uptime(void)
+static unsigned long get_uptime(void)
 {
 #ifdef __linux__
        struct sysinfo info;
@@ -78,12 +127,15 @@ static long get_uptime(void)
                return 0;
        return info.uptime;
 #elif 1
-       char buf[64];
-       long uptime;
+       unsigned long uptime;
+       char buf[sizeof(uptime)*3 + 2];
+       /* /proc/uptime is "UPTIME_SEC.NN IDLE_SEC.NN\n"
+        * (where IDLE is cumulative over all CPUs)
+        */
        if (open_read_close("/proc/uptime", buf, sizeof(buf)) <= 0)
-               bb_perror_msg_and_die("can't read %s", "/proc/uptime");
+               bb_perror_msg_and_die("can't read '%s'", "/proc/uptime");
        buf[sizeof(buf)-1] = '\0';
-       sscanf(buf, "%l", &uptime);
+       sscanf(buf, "%lu", &uptime);
        return uptime;
 #else
        struct timespec ts;
@@ -95,12 +147,6 @@ static long get_uptime(void)
 #endif
 
 #if ENABLE_DESKTOP
-
-#include <sys/times.h> /* for times() */
-#ifndef AT_CLKTCK
-# define AT_CLKTCK 17
-#endif
-
 /* TODO:
  * http://pubs.opengroup.org/onlinepubs/9699919799/utilities/ps.html
  * specifies (for XSI-conformant systems) following default columns
@@ -137,104 +183,28 @@ struct globals {
        char *buffer;
        unsigned terminal_width;
 #if ENABLE_FEATURE_PS_TIME
+# if ENABLE_FEATURE_PS_UNUSUAL_SYSTEMS || !defined(__linux__)
        unsigned kernel_HZ;
-       unsigned long long seconds_since_boot;
+# endif
+       unsigned long seconds_since_boot;
 #endif
 } FIX_ALIASING;
-#define G (*(struct globals*)&bb_common_bufsiz1)
+#define G (*(struct globals*)bb_common_bufsiz1)
 #define out                (G.out               )
 #define out_cnt            (G.out_cnt           )
 #define print_header       (G.print_header      )
 #define need_flags         (G.need_flags        )
 #define buffer             (G.buffer            )
 #define terminal_width     (G.terminal_width    )
-#define kernel_HZ          (G.kernel_HZ         )
-#define seconds_since_boot (G.seconds_since_boot)
-#define INIT_G() do { } while (0)
+#define INIT_G() do { setup_common_bufsiz(); } while (0)
 
 #if ENABLE_FEATURE_PS_TIME
-/* for ELF executables, notes are pushed before environment and args */
-static ptrdiff_t find_elf_note(ptrdiff_t findme)
-{
-       ptrdiff_t *ep = (ptrdiff_t *) environ;
-
-       while (*ep++)
-               continue;
-       while (*ep) {
-               if (ep[0] == findme) {
-                       return ep[1];
-               }
-               ep += 2;
-       }
-       return -1;
-}
-
-#if ENABLE_FEATURE_PS_UNUSUAL_SYSTEMS
-static unsigned get_HZ_by_waiting(void)
-{
-       struct timeval tv1, tv2;
-       unsigned t1, t2, r, hz;
-       unsigned cnt = cnt; /* for compiler */
-       int diff;
-
-       r = 0;
-
-       /* Wait for times() to reach new tick */
-       t1 = times(NULL);
-       do {
-               t2 = times(NULL);
-       } while (t2 == t1);
-       gettimeofday(&tv2, NULL);
-
-       do {
-               t1 = t2;
-               tv1.tv_usec = tv2.tv_usec;
-
-               /* Wait exactly one times() tick */
-               do {
-                       t2 = times(NULL);
-               } while (t2 == t1);
-               gettimeofday(&tv2, NULL);
-
-               /* Calculate ticks per sec, rounding up to even */
-               diff = tv2.tv_usec - tv1.tv_usec;
-               if (diff <= 0) diff += 1000000;
-               hz = 1000000u / (unsigned)diff;
-               hz = (hz+1) & ~1;
-
-               /* Count how many same hz values we saw */
-               if (r != hz) {
-                       r = hz;
-                       cnt = 0;
-               }
-               cnt++;
-       } while (cnt < 3); /* exit if saw 3 same values */
-
-       return r;
-}
-#else
-static inline unsigned get_HZ_by_waiting(void)
-{
-       /* Better method? */
-       return 100;
-}
-#endif
-
-static unsigned get_kernel_HZ(void)
-{
-
-       if (kernel_HZ)
-               return kernel_HZ;
-
-       /* Works for ELF only, Linux 2.4.0+ */
-       kernel_HZ = find_elf_note(AT_CLKTCK);
-       if (kernel_HZ == (unsigned)-1)
-               kernel_HZ = get_HZ_by_waiting();
-
-       seconds_since_boot = get_uptime();
-
-       return kernel_HZ;
-}
+# if ENABLE_FEATURE_PS_UNUSUAL_SYSTEMS || !defined(__linux__)
+#  define get_kernel_HZ() (G.kernel_HZ)
+# else
+    /* non-ancient Linux standardized on 100 for "times" freq */
+#  define get_kernel_HZ() ((unsigned)100)
+# endif
 #endif
 
 /* Print value to buf, max size+1 chars (including trailing '\0') */
@@ -293,13 +263,17 @@ static void func_pgid(char *buf, int size, const procps_status_t *ps)
        sprintf(buf, "%*u", size, ps->pgid);
 }
 
+static void func_sid(char *buf, int size, const procps_status_t *ps)
+{
+       sprintf(buf, "%*u", size, ps->sid);
+}
+
 static void put_lu(char *buf, int size, unsigned long u)
 {
        char buf4[5];
 
        /* see http://en.wikipedia.org/wiki/Tera */
-       smart_ulltoa4(u, buf4, " mgtpezy");
-       buf4[4] = '\0';
+       smart_ulltoa4(u, buf4, " mgtpezy")[0] = '\0';
        sprintf(buf, "%.*s", size, buf4);
 }
 
@@ -322,52 +296,71 @@ static void func_tty(char *buf, int size, const procps_status_t *ps)
 }
 
 #if ENABLE_FEATURE_PS_ADDITIONAL_COLUMNS
-
 static void func_rgroup(char *buf, int size, const procps_status_t *ps)
 {
        safe_strncpy(buf, get_cached_groupname(ps->rgid), size+1);
 }
-
 static void func_ruser(char *buf, int size, const procps_status_t *ps)
 {
        safe_strncpy(buf, get_cached_username(ps->ruid), size+1);
 }
-
 static void func_nice(char *buf, int size, const procps_status_t *ps)
 {
        sprintf(buf, "%*d", size, ps->niceness);
 }
-
 #endif
 
 #if ENABLE_FEATURE_PS_TIME
+static void format_time(char *buf, int size, unsigned long tt)
+{
+       unsigned ff;
+
+       /* Used to show "14453:50" if tt is large. Ugly.
+        * procps-ng 3.3.10 uses "[[dd-]hh:]mm:ss" format.
+        * TODO: switch to that?
+        */
 
+       /* Formatting for 5-char TIME column.
+        * NB: "size" is not always 5: ELAPSED is wider (7),
+        * not taking advantage of that (yet?).
+        */
+       ff = tt % 60;
+       tt /= 60;
+       if (tt < 60) {
+               snprintf(buf, size+1, "%2u:%02u", (unsigned)tt, ff);
+               return;
+       }
+       ff = tt % 60;
+       tt /= 60;
+       if (tt < 24) {
+               snprintf(buf, size+1, "%2uh%02u", (unsigned)tt, ff);
+               return;
+       }
+       ff = tt % 24;
+       tt /= 24;
+       if (tt < 100) {
+               snprintf(buf, size+1, "%2ud%02u", (unsigned)tt, ff);
+               return;
+       }
+       snprintf(buf, size+1, "%4lud", tt);
+}
 static void func_etime(char *buf, int size, const procps_status_t *ps)
 {
        /* elapsed time [[dd-]hh:]mm:ss; here only mm:ss */
        unsigned long mm;
-       unsigned ss;
 
        mm = ps->start_time / get_kernel_HZ();
-       /* must be after get_kernel_HZ()! */
-       mm = seconds_since_boot - mm;
-       ss = mm % 60;
-       mm /= 60;
-       snprintf(buf, size+1, "%3lu:%02u", mm, ss);
+       mm = G.seconds_since_boot - mm;
+       format_time(buf, size, mm);
 }
-
 static void func_time(char *buf, int size, const procps_status_t *ps)
 {
        /* cumulative time [[dd-]hh:]mm:ss; here only mm:ss */
        unsigned long mm;
-       unsigned ss;
 
        mm = (ps->utime + ps->stime) / get_kernel_HZ();
-       ss = mm % 60;
-       mm /= 60;
-       snprintf(buf, size+1, "%3lu:%02u", mm, ss);
+       format_time(buf, size, mm);
 }
-
 #endif
 
 #if ENABLE_SELINUX
@@ -378,11 +371,6 @@ static void func_label(char *buf, int size, const procps_status_t *ps)
 #endif
 
 /*
-static void func_nice(char *buf, int size, const procps_status_t *ps)
-{
-       ps->???
-}
-
 static void func_pcpu(char *buf, int size, const procps_status_t *ps)
 {
 }
@@ -407,11 +395,12 @@ static const ps_out_t out_spec[] = {
 //     { 5                  , "pcpu"  ,"%CPU"   ,func_pcpu  ,PSSCAN_        },
 #endif
 #if ENABLE_FEATURE_PS_TIME
-       { 6                  , "time"  ,"TIME"   ,func_time  ,PSSCAN_STIME | PSSCAN_UTIME },
+       { 5                  , "time"  ,"TIME"   ,func_time  ,PSSCAN_STIME | PSSCAN_UTIME },
 #endif
        { 6                  , "tty"   ,"TT"     ,func_tty   ,PSSCAN_TTY     },
        { 4                  , "vsz"   ,"VSZ"    ,func_vsz   ,PSSCAN_VSZ     },
 /* Not mandated, but useful: */
+       { 5                  , "sid"   ,"SID"    ,func_sid   ,PSSCAN_SID     },
        { 4                  , "stat"  ,"STAT"   ,func_state ,PSSCAN_STATE   },
        { 4                  , "rss"   ,"RSS"    ,func_rss   ,PSSCAN_RSS     },
 #if ENABLE_SELINUX
@@ -544,7 +533,7 @@ static void format_process(const procps_status_t *ps)
                len = out[i].width - len + 1;
                if (++i == out_cnt) /* do not pad last field */
                        break;
-               p += sprintf(p, "%*s", len, "");
+               p += sprintf(p, "%*s", len, " "); /* " ", not "", to ensure separation of fields */
        }
        printf("%.*s\n", terminal_width, buffer);
 }
@@ -562,7 +551,9 @@ int ps_main(int argc UNUSED_PARAM, char **argv)
        procps_status_t *p;
        llist_t* opt_o = NULL;
        char default_o[sizeof(DEFAULT_O_STR)];
+#if ENABLE_SELINUX || ENABLE_FEATURE_SHOW_THREADS
        int opt;
+#endif
        enum {
                OPT_Z = (1 << 0),
                OPT_o = (1 << 1),
@@ -576,6 +567,12 @@ int ps_main(int argc UNUSED_PARAM, char **argv)
        };
 
        INIT_G();
+#if ENABLE_FEATURE_PS_TIME
+       G.seconds_since_boot = get_uptime();
+# if ENABLE_FEATURE_PS_UNUSUAL_SYSTEMS || !defined(__linux__)
+       G.kernel_HZ = bb_clk_tck(); /* this is sysconf(_SC_CLK_TCK) */
+# endif
+#endif
 
        // POSIX:
        // -a  Write information for all processes associated with terminals
@@ -588,18 +585,23 @@ int ps_main(int argc UNUSED_PARAM, char **argv)
        // -o col1,col2,col3=header
        //     Select which columns to display
        /* We allow (and ignore) most of the above. FIXME.
-        * -T is picked for threads (POSIX hasn't it standardized).
+        * -T is picked for threads (POSIX hasn't standardized it).
         * procps v3.2.7 supports -T and shows tids as SPID column,
         * it also supports -L where it shows tids as LWP column.
         */
-       opt_complementary = "o::";
-       opt = getopt32(argv, "Zo:aAdefl"IF_FEATURE_SHOW_THREADS("T"), &opt_o);
+#if ENABLE_SELINUX || ENABLE_FEATURE_SHOW_THREADS
+       opt =
+#endif
+               getopt32(argv, "Zo:*aAdefl"IF_FEATURE_SHOW_THREADS("T"), &opt_o);
+
        if (opt_o) {
                do {
                        parse_o(llist_pop(&opt_o));
                } while (opt_o);
        } else {
-               /* Below: parse_o() needs char*, NOT const char*, can't give it default_o */
+               /* Below: parse_o() needs char*, NOT const char*,
+                * can't pass it constant string. Need to make a copy first.
+                */
 #if ENABLE_SELINUX
                if (!(opt & OPT_Z) || !is_selinux_enabled()) {
                        /* no -Z or no SELinux: do not show LABEL */
@@ -620,7 +622,7 @@ int ps_main(int argc UNUSED_PARAM, char **argv)
         * and such large widths */
        terminal_width = MAX_WIDTH;
        if (isatty(1)) {
-               get_terminal_width_height(0, &terminal_width, NULL);
+               terminal_width = get_terminal_width(0);
                if (--terminal_width > MAX_WIDTH)
                        terminal_width = MAX_WIDTH;
        }
@@ -652,32 +654,35 @@ int ps_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
                OPT_l = (1 << ENABLE_SELINUX) * (1 << ENABLE_FEATURE_SHOW_THREADS) * ENABLE_FEATURE_PS_LONG,
        };
 #if ENABLE_FEATURE_PS_LONG
-       time_t now = now;
-       long uptime;
+       time_t now = now; /* for compiler */
+       unsigned long uptime = uptime;
 #endif
-       int opts = 0;
        /* If we support any options, parse argv */
 #if ENABLE_SELINUX || ENABLE_FEATURE_SHOW_THREADS || ENABLE_FEATURE_PS_WIDE || ENABLE_FEATURE_PS_LONG
+       int opts = 0;
 # if ENABLE_FEATURE_PS_WIDE
        /* -w is a bit complicated */
        int w_count = 0;
-       opt_complementary = "-:ww";
-       opts = getopt32(argv, IF_SELINUX("Z")IF_FEATURE_SHOW_THREADS("T")IF_FEATURE_PS_LONG("l")
-                                       "w", &w_count);
+       make_all_argv_opts(argv);
+       opts = getopt32(argv, "^"
+               IF_SELINUX("Z")IF_FEATURE_SHOW_THREADS("T")IF_FEATURE_PS_LONG("l")"w"
+               "\0" "ww",
+               &w_count
+       );
        /* if w is given once, GNU ps sets the width to 132,
         * if w is given more than once, it is "unlimited"
         */
        if (w_count) {
                terminal_width = (w_count == 1) ? 132 : MAX_WIDTH;
        } else {
-               get_terminal_width_height(0, &terminal_width, NULL);
+               terminal_width = get_terminal_width(0);
                /* Go one less... */
                if (--terminal_width > MAX_WIDTH)
                        terminal_width = MAX_WIDTH;
        }
 # else
        /* -w is not supported, only -Z and/or -T */
-       opt_complementary = "-";
+       make_all_argv_opts(argv);
        opts = getopt32(argv, IF_SELINUX("Z")IF_FEATURE_SHOW_THREADS("T")IF_FEATURE_PS_LONG("l"));
 # endif
 
@@ -711,10 +716,10 @@ int ps_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
  * We also show STIME (standard says that -f shows it, -l doesn't).
  */
                puts("S   UID   PID  PPID   VSZ   RSS TTY   STIME TIME     CMD");
-#if ENABLE_FEATURE_PS_LONG
+# if ENABLE_FEATURE_PS_LONG
                now = time(NULL);
                uptime = get_uptime();
-#endif
+# endif
        }
        else {
                puts("  PID USER       VSZ STAT COMMAND");
@@ -737,8 +742,7 @@ int ps_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
 #endif
                {
                        char buf6[6];
-                       smart_ulltoa5(p->vsz, buf6, " mgtpezy");
-                       buf6[5] = '\0';
+                       smart_ulltoa5(p->vsz, buf6, " mgtpezy")[0] = '\0';
 #if ENABLE_FEATURE_PS_LONG
                        if (opts & OPT_l) {
                                char bufr[6], stime_str[6];
@@ -749,8 +753,7 @@ int ps_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
                                time_t start = now - elapsed;
                                struct tm *tm = localtime(&start);
 
-                               smart_ulltoa5(p->rss, bufr, " mgtpezy");
-                               bufr[5] = '\0';
+                               smart_ulltoa5(p->rss, bufr, " mgtpezy")[0] = '\0';
 
                                if (p->tty_major == 136)
                                        /* It should be pts/N, not ptsN, but N > 9
@@ -786,9 +789,11 @@ int ps_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
 
                {
                        int sz = terminal_width - len;
-                       char buf[sz + 1];
-                       read_cmdline(buf, sz, p->pid, p->comm);
-                       puts(buf);
+                       if (sz >= 0) {
+                               char buf[sz + 1];
+                               read_cmdline(buf, sz, p->pid, p->comm);
+                               puts(buf);
+                       }
                }
        }
        if (ENABLE_FEATURE_CLEAN_UP)