!345 add /proc/fd file to dump pid/fd information

Merge pull request !345 from LeonChan/proc_fd

fs/proc/include/internal.h

@@ -65,6 +65,8 @@ extern void ProcUptimeInit(void);
 
 extern void ProcFsCacheInit(void);
 
+extern void ProcFdInit(void);
+
 #ifdef __cplusplus
 #if __cplusplus
 }

fs/proc/os_adapt/fd_proc.c

+/*
+ * Copyright (c) 2021-2021 Huawei Device Co., Ltd. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without modification,
+ * are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this list of
+ *    conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice, this list
+ *    of conditions and the following disclaimer in the documentation and/or other materials
+ *    provided with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its contributors may be used
+ *    to endorse or promote products derived from this software without specific prior written
+ *    permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "proc_fs.h"
+
+#include <stdbool.h>
+#include "fs/file.h"
+#include "vfs_config.h"
+#include "internal.h"
+
+#include "fs/fd_table.h"
+#include "los_process.h"
+#include "capability_api.h"
+#include "capability_type.h"
+
+
+/*
+ * Template: Pid    Fd  [SysFd ] Name
+ */
+static void FillFdInfo(struct SeqBuf *seqBuf, struct filelist *fileList, unsigned int pid, bool hasPrivilege)
+{
+    int fd;
+    int sysFd;
+    char *name = NULL;
+    struct file *filp = NULL;
+
+    struct fd_table_s *fdt = LOS_GetFdTable(pid);
+    if ((fdt == NULL) || (fdt->proc_fds == NULL)) {
+        return;
+    }
+
+    (void)sem_wait(&fdt->ft_sem);
+
+    for (fd = MIN_START_FD; fd < fdt->max_fds; fd++) {
+        if (FD_ISSET(fd, fdt->proc_fds)) {
+            sysFd = fdt->ft_fds[fd].sysFd;
+            if (sysFd < CONFIG_NFILE_DESCRIPTORS) {
+                filp = &fileList->fl_files[sysFd];
+                name = filp->f_path;
+            } else if (sysFd < (CONFIG_NFILE_DESCRIPTORS + CONFIG_NSOCKET_DESCRIPTORS)) {
+                name = "(socks)";
+            } else if (sysFd < (FD_SETSIZE + CONFIG_NTIME_DESCRIPTORS)) {
+                name = "(timer)";
+            } else if (sysFd < (MQUEUE_FD_OFFSET + CONFIG_NQUEUE_DESCRIPTORS)) {
+                name = "(mqueue)";
+            } else {
+                name = "(unknown)";
+            }
+
+            if (hasPrivilege) {
+                (void)LosBufPrintf(seqBuf, "%u\t%d\t%d\t%s\n", pid, fd, sysFd, name);
+            } else {
+                (void)LosBufPrintf(seqBuf, "%u\t%d\t%s\n", pid, fd, name);
+            }
+        }
+    }
+
+    (void)sem_post(&fdt->ft_sem);
+}
+
+static int FdProcFill(struct SeqBuf *seqBuf, void *v)
+{
+    int pidNum;
+    bool hasPrivilege;
+    unsigned int pidMaxNum;
+    unsigned int *pidList = NULL;
+
+    /* privilege user */
+    if (IsCapPermit(CAP_DAC_READ_SEARCH)) {
+        pidMaxNum = LOS_GetSystemProcessMaximum();
+        pidList = (unsigned int *)malloc(pidMaxNum * sizeof(unsigned int));
+        if (pidList == NULL) {
+            return -ENOMEM;
+        }
+        pidNum = LOS_GetUsedPIDList(pidList, pidMaxNum);
+        hasPrivilege = true;
+        (void)LosBufPrintf(seqBuf, "Pid\tFd\tSysFd\tName\n");
+    } else {
+        pidNum = 1;
+        pidList = (unsigned int *)malloc(pidNum * sizeof(unsigned int));
+        if (pidList == NULL) {
+            return -ENOMEM;
+        }
+        pidList[0] = LOS_GetCurrProcessID();
+        hasPrivilege = false;
+        (void)LosBufPrintf(seqBuf, "Pid\tFd\tName\n");
+    }
+
+    struct filelist *fileList = &tg_filelist;
+    (void)sem_wait(&fileList->fl_sem);
+
+    for (int i = 0; i < pidNum; i++) {
+        FillFdInfo(seqBuf, fileList, pidList[i], hasPrivilege);
+    }
+
+    free(pidList);
+    (void)sem_post(&fileList->fl_sem);
+    return 0;
+}
+
+static const struct ProcFileOperations FD_PROC_FOPS = {
+    .read       = FdProcFill,
+};
+
+void ProcFdInit(void)
+{
+    struct ProcDirEntry *pde = CreateProcEntry("fd", 0, NULL);
+    if (pde == NULL) {
+        PRINT_ERR("creat /proc/fd error.\n");
+        return;
+    }
+
+    pde->procFileOps = &FD_PROC_FOPS;
+}
+

fs/proc/os_adapt/proc_init.c

@@ -65,6 +65,7 @@ void ProcFsInit(void)
     ProcUptimeInit();
     ProcKernelTraceInit();
     ProcFsCacheInit();
+    ProcFdInit();
 }
 
 LOS_MODULE_INIT(ProcFsInit, LOS_INIT_LEVEL_KMOD_EXTENDED);

kernel/base/core/los_process.c

@@ -1794,6 +1794,52 @@ LITE_OS_SEC_TEXT VOID LOS_Exit(INT32 status)
     OsProcessExit(OsCurrTaskGet(), (UINT32)status);
 }
 
+LITE_OS_SEC_TEXT INT32 LOS_GetUsedPIDList(UINT32 *pidList, INT32 pidMaxNum)
+{
+    LosProcessCB *pcb = NULL;
+    INT32 num = 0;
+    UINT32 intSave;
+    UINT32 pid = 1;
+
+    if (pidList == NULL) {
+        return 0;
+    }
+    SCHEDULER_LOCK(intSave);
+    while (OsProcessIDUserCheckInvalid(pid) == false) {
+        pcb = OS_PCB_FROM_PID(pid);
+        pid++;
+        if (OsProcessIsUnused(pcb)) {
+            continue;
+        }
+        pidList[num] = pcb->processID;
+        num++;
+        if (num >= pidMaxNum) {
+            break;
+        }
+    }
+    SCHEDULER_UNLOCK(intSave);
+    return num;
+}
+
+#ifdef LOSCFG_FS_VFS
+LITE_OS_SEC_TEXT struct fd_table_s *LOS_GetFdTable(UINT32 pid)
+{
+    LosProcessCB *pcb = NULL;
+    struct files_struct *files = NULL;
+
+    if (OS_PID_CHECK_INVALID(pid)) {
+        return NULL;
+    }
+    pcb = OS_PCB_FROM_PID(pid);
+    files = pcb->files;
+    if (files == NULL) {
+        return NULL;
+    }
+
+    return files->fdt;
+}
+#endif
+
 LITE_OS_SEC_TEXT UINT32 LOS_GetCurrProcessID(VOID)
 {
     return OsCurrProcessGet()->processID;

kernel/include/los_process.h

@@ -34,6 +34,10 @@
 
 #include "los_task.h"
 
+#ifdef LOSCFG_FS_VFS
+#include "fs/fd_table.h"
+#endif
+
 #ifdef __cplusplus
 #if __cplusplus
     extern "C" {
@@ -68,6 +72,12 @@ extern BOOL LOS_CheckInGroups(UINT32 gid);
 extern INT32 LOS_GetUserID(VOID);
 extern INT32 LOS_GetGroupID(VOID);
 
+extern INT32 LOS_GetUsedPIDList(UINT32 *pidList, INT32 pidMaxNum);
+
+#ifdef LOSCFG_FS_VFS
+struct fd_table_s *LOS_GetFdTable(UINT32 pid);
+#endif
+
 #ifdef __cplusplus
 #if __cplusplus
 }