Error handling

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/src/lttng-trace.c b/src/lttng-trace.c
index 3b0aafedb46f16693fabe49c51c94d18b063414f..aa6dcb7674c5fc769e0c86ee1c184d7647852854 100644 (file)
--- a/src/lttng-trace.c
+++ b/src/lttng-trace.c
@@ -122,7 +122,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
        if (ret) {
        //if (ptrace_ret) {
                PERROR("kill");
-               abort();
+               return -1;
        }
 
        for (;;) {
@@ -140,7 +140,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
                        }
                } else if (pid == 0) {
                        ERR("Unexpected PID 0");
-                       abort();
+                       return -1;
                } else {
                        if (WIFSTOPPED(status)) {
                                int shiftstatus, restartsig;
@@ -163,7 +163,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
                                        ptrace_ret = ptrace(PTRACE_GETEVENTMSG, pid, 0, &newpid);
                                        if (ptrace_ret) {
                                                PERROR("ptrace");
-                                               abort();
+                                               return -1;
                                        }
                                        DBG("Child pid %d is forking, child pid %ld", pid, newpid);
                                        for (i = 0; i < nr_handles; i++) {
@@ -178,7 +178,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
                                        ptrace_ret = ptrace(PTRACE_GETEVENTMSG, pid, 0, &newpid);
                                        if (ptrace_ret) {
                                                PERROR("ptrace");
-                                               abort();
+                                               return -1;
                                        }
                                        DBG("Child pid %d issuing vfork, child pid %ld", pid, newpid);
                                        for (i = 0; i < nr_handles; i++) {
@@ -193,7 +193,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
                                        ptrace_ret = ptrace(PTRACE_GETEVENTMSG, pid, 0, &newpid);
                                        if (ptrace_ret) {
                                                PERROR("ptrace");
-                                               abort();
+                                               return -1;
                                        }
                                        DBG("Child pid %d issuing clone, child pid %ld", pid, newpid);
                                        for (i = 0; i < nr_handles; i++) {
@@ -208,7 +208,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
                                        ptrace_ret = ptrace(PTRACE_GETEVENTMSG, pid, 0, &oldpid);
                                        if (ptrace_ret) {
                                                PERROR("ptrace");
-                                               abort();
+                                               return -1;
                                        }
                                        DBG("Child pid (old: %ld, new: %d) is issuing exec",
                                                        oldpid, pid);
@@ -260,7 +260,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
                                                ret = kill(pid, SIGTTIN);
                                                if (ret) {
                                                        PERROR("kill");
-                                                       abort();
+                                                       return -1;
                                                }
                                        } else if (status >> 16 == PTRACE_EVENT_STOP) {
                                                DBG("ptrace stop");
@@ -268,7 +268,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
                                                ptrace_ret = ptrace(PTRACE_CONT, pid, 0, 0);
                                                if (ptrace_ret) {
                                                        PERROR("ptrace cont");
-                                                       abort();
+                                                       return -1;
                                                }
                                        } else {
                                                DBG("job control stop ret %ld errno %d", ptrace_ret, errno);
@@ -279,7 +279,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
                                                ptrace_ret = ptrace(PTRACE_CONT, pid, 0, 0);
                                                if (ptrace_ret) {
                                                        PERROR("ptrace cont");
-                                                       abort();
+                                                       return -1;
                                                }
                                        }
                                        break;
@@ -296,7 +296,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
                                                ptrace_ret = ptrace(PTRACE_CONT, pid, 0, 0);
                                                if (ptrace_ret) {
                                                        PERROR("ptrace");
-                                                       abort();
+                                                       return -1;
                                                }
                                                break;
                                        //}
@@ -307,7 +307,7 @@ int wait_on_children(pid_t top_pid, struct lttng_handle **handle,
                                        ptrace_ret = ptrace(PTRACE_CONT, pid, 0, restartsig);
                                        if (ptrace_ret) {
                                                PERROR("ptrace");
-                                               abort();
+                                               return -1;
                                        }
                                }
                        } else if (WIFEXITED(status)) {
@@ -402,29 +402,39 @@ int enable_syscalls(struct lttng_trace_ctx *ctx)
        struct lttng_domain domain;
        struct lttng_event *ev;
        struct lttng_handle *handle;
-       int ret;
+       int ret = 0;
 
        if (opt_no_syscall)
                return 0;
        memset(&domain, 0, sizeof(domain));
        ev = lttng_event_create();
-       if (!ev)
-               abort();
+       if (!ev) {
+               ERR("Error creating event");
+               goto end;
+       }
        domain.type = LTTNG_DOMAIN_KERNEL;
        domain.buf_type = LTTNG_BUFFER_GLOBAL;
 
        handle = lttng_create_handle(ctx->session_name, &domain);
-       if (!handle)
-               abort();
+       if (!handle) {
+               ERR("Error creating handle");
+               ret = -1;
+               goto error_handle;
+       }
        ev->type = LTTNG_EVENT_SYSCALL;
        strcpy(ev->name, "*");
        ev->loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
        ret = lttng_enable_event_with_exclusions(handle,
                        ev, NULL, NULL, 0, NULL);
-       if (ret)
-               abort();
+       if (ret) {
+               ERR("Error enabling syscall events");
+               ret = -1;
+       }
        lttng_destroy_handle(handle);
-       return 0;
+error_handle:
+       lttng_event_destroy(ev);
+end:
+       return ret;
 }
 
 static
@@ -433,6 +443,8 @@ int add_contexts(struct lttng_trace_ctx *ctx, enum lttng_domain_type domain_type
        struct lttng_domain domain;
        struct lttng_event_context event_ctx;
        struct lttng_handle *handle;
+       const char *domain_str;
+       int ret = 0;
 
        if (opt_no_context)
                return 0;
@@ -440,9 +452,11 @@ int add_contexts(struct lttng_trace_ctx *ctx, enum lttng_domain_type domain_type
        switch (domain_type) {
        case LTTNG_DOMAIN_KERNEL:
                domain.buf_type = LTTNG_BUFFER_GLOBAL;
+               domain_str = "kernel";
                break;
        case LTTNG_DOMAIN_UST:
                domain.buf_type = LTTNG_BUFFER_PER_UID;
+               domain_str = "ust";
                break;
        default:
                return -1;
@@ -450,26 +464,37 @@ int add_contexts(struct lttng_trace_ctx *ctx, enum lttng_domain_type domain_type
        domain.type = domain_type;
 
        handle = lttng_create_handle(ctx->session_name, &domain);
-       if (!handle)
-               abort();
-
+       if (!handle) {
+               ERR("Error creating handle");
+               ret = -1;
+               goto end;
+       }
        memset(&event_ctx, 0, sizeof(event_ctx));
        event_ctx.ctx = LTTNG_EVENT_CONTEXT_PROCNAME;
-       if (lttng_add_context(handle, &event_ctx, NULL, NULL) < 0)
-               abort();
-
+       if (lttng_add_context(handle, &event_ctx, NULL, NULL) < 0) {
+               ERR("Error adding `procname` context to domain `%s`", domain_str);
+               ret = -1;
+               goto error_context;
+       }
        memset(&event_ctx, 0, sizeof(event_ctx));
        event_ctx.ctx = LTTNG_EVENT_CONTEXT_VPID;
-       if (lttng_add_context(handle, &event_ctx, NULL, NULL) < 0)
-               abort();
-
+       if (lttng_add_context(handle, &event_ctx, NULL, NULL) < 0) {
+               ERR("Error adding `vpid` context to domain `%s`", domain_str);
+               ret = -1;
+               goto error_context;
+       }
        memset(&event_ctx, 0, sizeof(event_ctx));
        event_ctx.ctx = LTTNG_EVENT_CONTEXT_VTID;
-       if (lttng_add_context(handle, &event_ctx, NULL, NULL) < 0)
-               abort();
+       if (lttng_add_context(handle, &event_ctx, NULL, NULL) < 0) {
+               ERR("Error adding `vtid` context to domain `%s`", domain_str);
+               ret = -1;
+               goto error_context;
+       }
 
+error_context:
        lttng_destroy_handle(handle);
-       return 0;
+end:
+       return ret;
 }
 
 static
@@ -478,31 +503,46 @@ int create_channels(struct lttng_trace_ctx *ctx, enum lttng_domain_type domain_t
        struct lttng_domain domain;
        struct lttng_channel *channel;
        struct lttng_handle *handle;
+       const char *domain_str;
+       int ret = 0;
 
        memset(&domain, 0, sizeof(domain));
        switch (domain_type) {
        case LTTNG_DOMAIN_KERNEL:
                domain.buf_type = LTTNG_BUFFER_GLOBAL;
+               domain_str = "kernel";
                break;
        case LTTNG_DOMAIN_UST:
                domain.buf_type = LTTNG_BUFFER_PER_UID;
+               domain_str = "ust";
                break;
        default:
                return -1;
        }
        domain.type = domain_type;
        channel = lttng_channel_create(&domain);
+       if (!channel) {
+               ERR("Error creating channel for domain `%s`", domain_str);
+               ret = -1;
+               goto end;
+       }
        channel->enabled = 1;
 
        handle = lttng_create_handle(ctx->session_name, &domain);
-       if (!handle)
-               abort();
-       if (lttng_enable_channel(handle, channel) < 0)
-               abort();
+       if (!handle) {
+               ERR("Error creating handle");
+               ret = -1;
+               goto error_handle;
+       }
+       if (lttng_enable_channel(handle, channel) < 0) {
+               ERR("Error enabling channel for domain `%s`", domain_str);
+               ret = -1;
+       }
        lttng_destroy_handle(handle);
-
+error_handle:
        lttng_channel_destroy(channel);
-       return 0;
+end:
+       return ret;
 }
 
 static
@@ -548,16 +588,21 @@ int lttng_trace_ctx_init(struct lttng_trace_ctx *ctx, const char *cmd_name)
        struct tm *timeinfo;
 
        ctx->creation_time = time(NULL);
-       if (ctx->creation_time == (time_t) -1)
-               abort();
+       if (ctx->creation_time == (time_t) -1) {
+               PERROR("time");
+               return -1;
+       }
        timeinfo = localtime(&ctx->creation_time);
-       if (!timeinfo)
-               abort();
+       if (!timeinfo) {
+               PERROR("localtime");
+               return -1;
+       }
        strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
 
        if (opt_session) {
                if (strlen(session_name) > LTTNG_NAME_MAX - 1) {
-                       abort();
+                       ERR("Session name is too long");
+                       return -1;
                }
                strcpy(ctx->session_name, session_name);
        } else {
@@ -570,7 +615,8 @@ int lttng_trace_ctx_init(struct lttng_trace_ctx *ctx, const char *cmd_name)
 
        if (opt_output) {
                if (strlen(output_path) > PATH_MAX - 1) {
-                       abort();
+                       ERR("output path is too long");
+                       return -1;
                }
                strcpy(ctx->path, output_path);
        } else {
@@ -591,7 +637,6 @@ int lttng_trace_untrack_all(struct lttng_handle **handle,
                ret = lttng_untrack_pid(handle[i], -1);
                if (ret && ret != -LTTNG_ERR_INVALID) {
                        ERR("Error %d untracking pid %d", ret, -1);
-                       abort();
                }
        }
        return 0;
@@ -697,19 +742,27 @@ int main(int argc, char **argv)
                return EXIT_SUCCESS;
        }
 
-       if (lttng_trace_ctx_init(&ptrace_ctx, argv[skip_args]))
-               abort();
+       if (lttng_trace_ctx_init(&ptrace_ctx, argv[skip_args])) {
+               ERR("Error initializing trace context");
+               retval = -1;
+               goto end;
+       }
 
        act.sa_sigaction = sighandler;
        act.sa_flags = SA_SIGINFO | SA_RESTART;
        sigemptyset(&act.sa_mask);
        ret = sigaction(SIGTERM, &act, NULL);
-       if (ret)
-               abort();
+       if (ret) {
+               PERROR("sigaction");
+               retval = -1;
+               goto end;
+       }
        ret = sigaction(SIGINT, &act, NULL);
-       if (ret)
-               abort();
-
+       if (ret) {
+               PERROR("sigaction");
+               retval = -1;
+               goto end;
+       }
        if (create_session(&ptrace_ctx) < 0) {
                fprintf(stderr, "%sError: Unable to create tracing session. Please ensure that lttng-sessiond is running as root and that your user belongs to the `tracing` group.\n", MESSAGE_PREFIX);
                retval = -1;
@@ -782,8 +835,10 @@ end_wait_on_children:
 end_ust_handle:
        lttng_destroy_handle(handle[0]);
 end_kernel_handle:
-       if (destroy_session(&ptrace_ctx))
-               abort();
+       if (destroy_session(&ptrace_ctx)) {
+               ERR("Error destroying session");
+               retval = -1;
+       }
 end:
        if (retval) {
                return EXIT_FAILURE;