--- /dev/null
+/**
+ * collectd - src/utils/proc_pids/proc_pids.c
+ *
+ * Copyright(c) 2018-2019 Intel Corporation. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * Authors:
+ * Starzyk, Mateusz <mateuszx.starzyk@intel.com>
+ * Wojciech Andralojc <wojciechx.andralojc@intel.com>
+ * Michał Aleksiński <michalx.aleksinski@intel.com>
+ **/
+
+#include "collectd.h"
+#include "utils/common/common.h"
+#include "utils/proc_pids/proc_pids.h"
+
+#define UTIL_NAME "utils_proc_pids"
+
+void pids_list_free(pids_list_t *list) {
+ assert(list);
+
+ sfree(list->pids);
+ sfree(list);
+}
+
+int proc_pids_is_name_valid(const char *name) {
+
+ if (name != NULL) {
+ unsigned len = strlen(name);
+ if (len > 0 && len <= MAX_PROC_NAME_LEN)
+ return 1;
+ else {
+ DEBUG(UTIL_NAME
+ ": Process name \'%s\' is too long. Max supported len is %d chars.",
+ name, MAX_PROC_NAME_LEN);
+ }
+ }
+
+ return 0;
+}
+
+int pids_list_add_pid(pids_list_t *list, const pid_t pid) {
+ assert(list);
+
+ if (list->allocated == list->size) {
+ size_t new_allocated = list->allocated + 1 + list->allocated / 10;
+ pid_t *new_pids = realloc(list->pids, sizeof(pid_t) * new_allocated);
+
+ if (NULL == new_pids) {
+ ERROR(UTIL_NAME ": Alloc error\n");
+ return -1;
+ }
+
+ list->pids = new_pids;
+ list->allocated = new_allocated;
+ }
+
+ list->pids[list->size] = pid;
+ list->size++;
+
+ return 0;
+}
+
+int pids_list_add_list(pids_list_t *dst, pids_list_t *src) {
+ assert(dst);
+ assert(src);
+
+ if (dst->allocated < dst->size + src->size) {
+ pid_t *new_pids =
+ realloc(dst->pids, sizeof(pid_t) * (dst->size + src->size));
+
+ if (NULL == new_pids) {
+ ERROR(UTIL_NAME ": Alloc error\n");
+ return -1;
+ }
+
+ dst->allocated = dst->size + src->size;
+ dst->pids = new_pids;
+ }
+
+ memcpy(dst->pids + dst->size, src->pids, src->size * sizeof(*(src->pids)));
+ dst->size += src->size;
+
+ return 0;
+}
+
+int pids_list_clear(pids_list_t *list) {
+ assert(list);
+
+ if (list->pids != NULL)
+ sfree(list->pids);
+
+ list->size = 0;
+ list->allocated = 0;
+
+ return 0;
+}
+
+int pids_list_contains_pid(pids_list_t *list, const pid_t pid) {
+ assert(list);
+
+ for (int i = 0; i < list->size; i++)
+ if (list->pids[i] == pid)
+ return 1;
+
+ return 0;
+}
+
+/*
+ * NAME
+ * read_proc_name
+ *
+ * DESCRIPTION
+ * Reads process name from given pid directory.
+ * Strips new-line character (\n).
+ *
+ * PARAMETERS
+ * `procfs_path' Path to systems proc directory (e.g. /proc)
+ * `pid_entry' Dirent for PID directory
+ * `name' Output buffer for process name, recommended proc_comm.
+ * `out_size' Output buffer size, recommended sizeof(proc_comm)
+ *
+ * RETURN VALUE
+ * On success, the number of read bytes (includes stripped \n).
+ * -1 on file open error
+*/
+static int read_proc_name(const char *procfs_path,
+ const struct dirent *pid_entry, char *name,
+ const size_t out_size) {
+ assert(pid_entry);
+ assert(name);
+ assert(out_size);
+ memset(name, 0, out_size);
+
+ const char *comm_file_name = "comm";
+
+ char *path = ssnprintf_alloc("%s/%s/%s", procfs_path, pid_entry->d_name,
+ comm_file_name);
+ if (path == NULL)
+ return -1;
+ FILE *f = fopen(path, "r");
+ if (f == NULL) {
+ ERROR(UTIL_NAME ": Failed to open comm file, error: %d\n", errno);
+ sfree(path);
+ return -1;
+ }
+ size_t read_length = fread(name, sizeof(char), out_size, f);
+ name[out_size - 1] = '\0';
+ fclose(f);
+ sfree(path);
+ /* strip new line ending */
+ char *newline = strchr(name, '\n');
+ if (newline) {
+ *newline = '\0';
+ }
+
+ return read_length;
+}
+
+/*
+ * NAME
+ * get_pid_number
+ *
+ * DESCRIPTION
+ * Gets pid number for given /proc/pid directory entry or
+ * returns error if input directory does not hold PID information.
+ *
+ * PARAMETERS
+ * `entry' Dirent for PID directory
+ * `pid' PID number to be filled
+ *
+ * RETURN VALUE
+ * 0 on success. -1 on error.
+ */
+static int get_pid_number(struct dirent *entry, pid_t *pid) {
+ char *tmp_end; /* used for strtoul error check*/
+
+ if (pid == NULL || entry == NULL)
+ return -1;
+
+ if (entry->d_type != DT_DIR)
+ return -1;
+
+ /* trying to get pid number from directory name*/
+ *pid = strtoul(entry->d_name, &tmp_end, 10);
+ if (*tmp_end != '\0') {
+ return -1; /* conversion failed, not proc-pid */
+ }
+ /* all checks passed, marking as success */
+ return 0;
+}
+
+int proc_pids_init(const char **procs_names_array,
+ const size_t procs_names_array_size,
+ proc_pids_t **proc_pids[]) {
+
+ proc_pids_t **proc_pids_array;
+ assert(proc_pids);
+ assert(NULL == *proc_pids);
+
+ /* Copy procs names to output array. Initialize pids list with NULL value. */
+ proc_pids_array = calloc(procs_names_array_size, sizeof(*proc_pids_array));
+
+ if (NULL == proc_pids_array)
+ return -1;
+
+ for (size_t i = 0; i < procs_names_array_size; ++i) {
+ proc_pids_array[i] = calloc(1, sizeof(**proc_pids_array));
+ if (NULL == proc_pids_array[i])
+ goto proc_pids_init_error;
+
+ sstrncpy(proc_pids_array[i]->process_name, procs_names_array[i],
+ STATIC_ARRAY_SIZE(proc_pids_array[i]->process_name));
+ proc_pids_array[i]->prev = NULL;
+ proc_pids_array[i]->curr = NULL;
+ }
+
+ *proc_pids = proc_pids_array;
+
+ return 0;
+proc_pids_init_error:
+ if (NULL != proc_pids_array) {
+ for (size_t i = 0; i < procs_names_array_size; ++i) {
+ free(proc_pids_array[i]);
+ }
+ free(proc_pids_array);
+ }
+ return -1;
+}
+
+static void swap_proc_pids(proc_pids_t **proc_pids, size_t proc_pids_num) {
+ for (size_t i = 0; i < proc_pids_num; i++) {
+ pids_list_t *swap = proc_pids[i]->prev;
+ proc_pids[i]->prev = proc_pids[i]->curr;
+ proc_pids[i]->curr = swap;
+ }
+}
+
+int proc_pids_update(const char *procfs_path, proc_pids_t **proc_pids,
+ size_t proc_pids_num) {
+ assert(procfs_path);
+ assert(proc_pids);
+
+ DIR *proc_dir = opendir(procfs_path);
+ if (proc_dir == NULL) {
+ ERROR(UTIL_NAME ": Could not open %s directory, error: %d", procfs_path,
+ errno);
+ return -1;
+ }
+
+ swap_proc_pids(proc_pids, proc_pids_num);
+
+ for (size_t i = 0; i < proc_pids_num; i++) {
+ if (NULL == proc_pids[i]->curr)
+ proc_pids[i]->curr = calloc(1, sizeof(*(proc_pids[i]->curr)));
+
+ if (NULL == proc_pids[i]->curr) {
+ ERROR(UTIL_NAME ": Alloc error\n");
+ goto update_error;
+ }
+
+ proc_pids[i]->curr->size = 0;
+ }
+
+ /* Go through procfs and find PIDS and their comms */
+ struct dirent *entry;
+ while ((entry = readdir(proc_dir)) != NULL) {
+ pid_t pid;
+ int pid_conversion = get_pid_number(entry, &pid);
+ if (pid_conversion < 0)
+ continue;
+
+ proc_comm_t comm;
+ int read_result =
+ read_proc_name(procfs_path, entry, comm, sizeof(proc_comm_t));
+ if (read_result <= 0)
+ continue;
+
+ /* Try to find comm in input procs array */
+ for (size_t i = 0; i < proc_pids_num; ++i) {
+ if (0 ==
+ strncmp(comm, proc_pids[i]->process_name, STATIC_ARRAY_SIZE(comm)))
+ pids_list_add_pid(proc_pids[i]->curr, pid);
+ }
+ }
+
+ int close_result = closedir(proc_dir);
+ if (0 != close_result) {
+ ERROR(UTIL_NAME ": failed to close /proc directory, error: %d", errno);
+ goto update_error;
+ }
+ return 0;
+
+update_error:
+ swap_proc_pids(proc_pids, proc_pids_num);
+ return -1;
+}
+
+int pids_list_diff(proc_pids_t *proc, pids_list_t *added,
+ pids_list_t *removed) {
+ assert(proc);
+ assert(added);
+ assert(removed);
+
+ added->size = 0;
+ removed->size = 0;
+
+ if (NULL == proc->prev || 0 == proc->prev->size) {
+ /* append all PIDs from curr to added*/
+ return pids_list_add_list(added, proc->curr);
+ } else if (NULL == proc->curr || 0 == proc->curr->size) {
+ /* append all PIDs from prev to removed*/
+ return pids_list_add_list(removed, proc->prev);
+ }
+
+ for (int i = 0; i < proc->prev->size; i++)
+ if (0 == pids_list_contains_pid(proc->curr, proc->prev->pids[i])) {
+ int add_result = pids_list_add_pid(removed, proc->prev->pids[i]);
+ if (add_result < 0)
+ return add_result;
+ }
+
+ for (int i = 0; i < proc->curr->size; i++)
+ if (0 == pids_list_contains_pid(proc->prev, proc->curr->pids[i])) {
+ int add_result = pids_list_add_pid(added, proc->curr->pids[i]);
+ if (add_result < 0)
+ return add_result;
+ }
+
+ return 0;
+}
+
+int proc_pids_free(proc_pids_t *proc_pids[], size_t proc_pids_num) {
+ for (size_t i = 0; i < proc_pids_num; i++) {
+ if (NULL != proc_pids[i]->curr)
+ pids_list_free(proc_pids[i]->curr);
+ if (NULL != proc_pids[i]->prev)
+ pids_list_free(proc_pids[i]->prev);
+ sfree(proc_pids[i]);
+ }
+ sfree(proc_pids);
+
+ return 0;
+}