utrace: Sort syscalls by number of invocations

[project/procd.git] / trace / trace.c

diff --git a/trace/trace.c b/trace/trace.c
index 662010e..35bc548 100644 (file)
--- a/trace/trace.c
+++ b/trace/trace.c
@@ -77,6 +77,16 @@ static void set_syscall(const char *name, int val)
                }
 }
 
                }
 }
 

+struct syscall {
+       int syscall;
+       int count;
+};
+
+static int cmp_count(const void *a, const void *b)
+{
+       return ((struct syscall*)b)->count - ((struct syscall*)a)->count;
+}
+

 static void print_syscalls(int policy, const char *json)
 {
        void *c;
 static void print_syscalls(int policy, const char *json)
 {
        void *c;


@@ -88,19 +98,29 @@ static void print_syscalls(int policy, const char *json)
        set_syscall("exit_group", 1);
        set_syscall("exit", 1);
 
        set_syscall("exit_group", 1);
        set_syscall("exit", 1);
 

+       struct syscall sorted[ARRAY_SIZE(syscall_names)];
+
+       for (i = 0; i < ARRAY_SIZE(syscall_names); i++) {
+               sorted[i].syscall = i;
+               sorted[i].count = syscall_count[i];
+       }
+
+       qsort(sorted, ARRAY_SIZE(syscall_names), sizeof(sorted[0]), cmp_count);
+

        blob_buf_init(&b, 0);
        c = blobmsg_open_array(&b, "whitelist");
 
        for (i = 0; i < ARRAY_SIZE(syscall_names); i++) {
        blob_buf_init(&b, 0);
        c = blobmsg_open_array(&b, "whitelist");
 
        for (i = 0; i < ARRAY_SIZE(syscall_names); i++) {

-               if (!syscall_count[i])
-                       continue;
-               if (syscall_names[i]) {
+               int sc = sorted[i].syscall;
+               if (!sorted[i].count)
+                       break;
+               if (syscall_names[sc]) {

                        if (debug)
                                printf("syscall %d (%s) was called %d times\n",
                        if (debug)
                                printf("syscall %d (%s) was called %d times\n",

-                                       i, syscall_names[i], syscall_count[i]);
-                       blobmsg_add_string(&b, NULL, syscall_names[i]);
+                                       sc, syscall_names[sc], sorted[i].count);
+                       blobmsg_add_string(&b, NULL, syscall_names[sc]);

                } else {
                } else {

-                       ERROR("no name found for syscall(%d)\n", i);
+                       ERROR("no name found for syscall(%d)\n", sc);

                }
        }
        blobmsg_close_array(&b, c);
                }
        }
        blobmsg_close_array(&b, c);


@@ -177,7 +197,7 @@ int main(int argc, char **argv, char **envp)
                char **_argv = calloc(argc + 1, sizeof(char *));
                char **_envp;
                char *preload = "LD_PRELOAD=/lib/libpreload-trace.so";
                char **_argv = calloc(argc + 1, sizeof(char *));
                char **_envp;
                char *preload = "LD_PRELOAD=/lib/libpreload-trace.so";

-               int envc = 1;
+               int envc = 0;

                int ret;
 
                memcpy(_argv, argv, argc * sizeof(char *));
                int ret;
 
                memcpy(_argv, argv, argc * sizeof(char *));


@@ -185,11 +205,11 @@ int main(int argc, char **argv, char **envp)
                while (envp[envc++])
                        ;
 
                while (envp[envc++])
                        ;
 

-               _envp = calloc(envc, sizeof(char *));
-               memcpy(&_envp[1], _envp, envc * sizeof(char *));
-               *envp = preload;
+               _envp = calloc(envc + 1, sizeof(char *));
+               memcpy(&_envp[1], envp, envc * sizeof(char *));
+               *_envp = preload;

 
 

-               ret = execve(_argv[0], _argv, envp);
+               ret = execve(_argv[0], _argv, _envp);

                ERROR("failed to exec %s: %s\n", _argv[0], strerror(errno));
 
                free(_argv);
                ERROR("failed to exec %s: %s\n", _argv[0], strerror(errno));
 
                free(_argv);