ps: add flag to show ABI

Allow us to easily identify the 32/64 bitness of the process. Yes, I
know this is not technically an ABI, but it seemed close enough!

Change-Id: Ia03a17fd74d61e7619911cb26b3dd7d82b62930c

1 files changed, 47 insertions, 4 deletions

diff --git a/toolbox/ps.c b/toolbox/ps.c
index 7c35ccb..e9fba0b 100644
--- a/toolbox/ps.c
+++ b/toolbox/ps.c
@@ -28,9 +28,12 @@ static char *nexttok(char **strp)
 #define SHOW_POLICY 4
 #define SHOW_CPU  8
 #define SHOW_MACLABEL 16
+#define SHOW_ABI 32
 
 static int display_flags = 0;
 
+static void print_exe_abi(int pid);
+
 static int ps_line(int pid, int tid, char *namefilter)
 {
     char statline[1024];
@@ -170,7 +173,11 @@ static int ps_line(int pid, int tid, char *namefilter)
             else
                 printf(" %.2s ", get_sched_policy_name(p));
         }
-        printf(" %08x %08x %s %s", wchan, eip, state, cmdline[0] ? cmdline : name);
+        printf(" %08x %08x %s ", wchan, eip, state);
+        if (display_flags & SHOW_ABI) {
+            print_exe_abi(pid);
+        }
+        printf("%s", cmdline[0] ? cmdline : name);
         if(display_flags&SHOW_TIME)
             printf(" (u:%d, s:%d)", utime, stime);
 
@@ -179,6 +186,39 @@ static int ps_line(int pid, int tid, char *namefilter)
     return 0;
 }
 
+static void print_exe_abi(int pid)
+{
+    int fd, r;
+    char exeline[1024];
+
+    sprintf(exeline, "/proc/%d/exe", pid);
+    fd = open(exeline, O_RDONLY);
+    if(fd == 0) {
+        printf("    ");
+        return;
+    }
+    r = read(fd, exeline, 5 /* 4 byte ELFMAG + 1 byte EI_CLASS */);
+    close(fd);
+    if(r < 0) {
+        printf("    ");
+        return;
+    }
+    if (memcmp("\177ELF", exeline, 4) != 0) {
+        printf("??  ");
+        return;
+    }
+    switch (exeline[4]) {
+        case 1:
+            printf("32  ");
+            return;
+        case 2:
+            printf("64  ");
+            return;
+        default:
+            printf("??  ");
+            return;
+    }
+}
 
 void ps_threads(int pid, char *namefilter)
 {
@@ -224,7 +264,9 @@ int ps_main(int argc, char **argv)
             display_flags |= SHOW_PRIO;
         } else if(!strcmp(argv[1],"-c")) {
             display_flags |= SHOW_CPU;
-        }  else if(isdigit(argv[1][0])){
+        } else if(!strcmp(argv[1],"--abi")) {
+            display_flags |= SHOW_ABI;
+        } else if(isdigit(argv[1][0])){
             pidfilter = atoi(argv[1]);
         } else {
             namefilter = argv[1];
@@ -236,10 +278,11 @@ int ps_main(int argc, char **argv)
     if (display_flags & SHOW_MACLABEL) {
         printf("LABEL                          USER     PID   PPID  NAME\n");
     } else {
-        printf("USER     PID   PPID  VSIZE  RSS   %s%s %s WCHAN    PC         NAME\n",
+        printf("USER     PID   PPID  VSIZE  RSS   %s%s %s WCHAN    PC        %sNAME\n",
                (display_flags&SHOW_CPU)?"CPU ":"",
                (display_flags&SHOW_PRIO)?"PRIO  NICE  RTPRI SCHED ":"",
-               (display_flags&SHOW_POLICY)?"PCY " : "");
+               (display_flags&SHOW_POLICY)?"PCY " : "",
+               (display_flags&SHOW_ABI)?"ABI " : "");
     }
     while((de = readdir(d)) != 0){
         if(isdigit(de->d_name[0])){