proc_file.c 文件参考

浏览源代码.

函数
	DEFINE_SPINLOCK (procfsLock)
int	ProcMatch (unsigned int len, const char *name, struct ProcDirEntry *pn)
static struct ProcDirEntry *	ProcFindNode (struct ProcDirEntry *parent, const char *name)
struct ProcDirEntry *	ProcFindEntry (const char *path)
static int	CheckProcName (const char *name, struct ProcDirEntry **parent, const char **lastName)
	检查 proc名称有效性 更多...
static struct ProcDirEntry *	ProcAllocNode (struct ProcDirEntry **parent, const char *name, mode_t mode)
	分配 proc 节点 更多...
static int	ProcAddNode (struct ProcDirEntry *parent, struct ProcDirEntry *pn)
static void	ProcDetachNode (struct ProcDirEntry *pn)
static struct ProcDirEntry *	ProcCreateDir (struct ProcDirEntry *parent, const char *name, const struct ProcFileOperations *procFileOps, mode_t mode)
	/proc文件系统创建目录的方式 更多...
static struct ProcDirEntry *	ProcCreateFile (struct ProcDirEntry *parent, const char *name, const struct ProcFileOperations *procFileOps, mode_t mode)
	创建文件项 更多...
struct ProcDirEntry *	CreateProcEntry (const char *name, mode_t mode, struct ProcDirEntry *parent)
	创建 pro (目录/文件)项 更多...
static void	FreeProcEntry (struct ProcDirEntry *entry)
	释放proc 更多...
void	ProcFreeEntry (struct ProcDirEntry *pn)
	释放 更多...
static void	RemoveProcEntryTravalsal (struct ProcDirEntry *pn)
void	RemoveProcEntry (const char *name, struct ProcDirEntry *parent)
	remove a proc node 更多...
struct ProcDirEntry *	ProcMkdirMode (const char *name, mode_t mode, struct ProcDirEntry *parent)
struct ProcDirEntry *	ProcMkdir (const char *name, struct ProcDirEntry *parent)
	create a proc directory node 更多...
struct ProcDirEntry *	ProcCreateData (const char *name, mode_t mode, struct ProcDirEntry *parent, const struct ProcFileOperations *procFileOps, void *data)
	创建数据 更多...
struct ProcDirEntry *	ProcCreate (const char *name, mode_t mode, struct ProcDirEntry *parent, const struct ProcFileOperations *procFileOps)
	create a proc node 更多...
int	ProcStat (const char *file, struct ProcStat *buf)
static int	GetNextDir (struct ProcDirEntry *pn, void *buf, size_t len)
int	ProcOpen (struct ProcFile *procFile)
	打开 pro 更多...
static int	ProcRead (struct ProcDirEntry *pde, char *buf, size_t len)
struct ProcDirEntry *	OpenProcFile (const char *fileName, int flags,...)
	open a proc node 更多...
int	ReadProcFile (struct ProcDirEntry *pde, void *buf, size_t len)
	read a proc node 更多...
int	WriteProcFile (struct ProcDirEntry *pde, const void *buf, size_t len)
	写 proc 文件 更多...
loff_t	LseekProcFile (struct ProcDirEntry *pde, loff_t offset, int whence)
	seek proc 文件 更多...
int	LseekDirProcFile (struct ProcDirEntry *pde, off_t *pos, int whence)
	directory migration 更多...
int	CloseProcFile (struct ProcDirEntry *pde)
	close a proc node 更多...
struct ProcDirEntry *	GetProcRootEntry (void)

变量
bool	procfsInit = false
static struct ProcFile	g_procPf
static struct ProcDirEntry	g_procRootDirEntry

函数说明

CheckProcName()

static int CheckProcName ( const char *  name, struct ProcDirEntry **  parent, const char **  lastName  )

static

检查 proc名称有效性

在文件 proc_file.c 第 166 行定义.

{
    struct ProcDirEntry *pn = *parent;
    const char *segment = name;
    const char *restName = NULL;
    int length;
 
    if (pn == NULL) {
        pn = &g_procRootDirEntry;
    }
 
    spin_lock(&procfsLock);
 
    restName = strchr(segment, '/');
    for (; restName != NULL; restName = strchr(segment, '/')) {
        length = restName - segment;
        for (pn = pn->subdir; pn != NULL; pn = pn->next) {
            if (ProcMatch(length, segment, pn)) {
                break;
            }
        }
        if (pn == NULL) {
            PRINT_ERR(" Error!No such name '%s'\n", name);
            spin_unlock(&procfsLock);
            return -ENOENT;
        }
        segment = restName;
        segment++;
    }
    *lastName = segment;
    *parent = pn;
    spin_unlock(&procfsLock);
 
    return 0;
}

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CloseProcFile()

int CloseProcFile

(

struct ProcDirEntry *

pde

)

close a proc node

Description:

This API is used to close the node by pde

注意

• None.

参数

pde	[IN] Type #struct ProcDirEntry * pointer of the node structure to be closed

返回值

#-1	close failed
#0	close successfully

Dependency:

• proc_fs.h: the header file that contains the API declaration.

参见

proc_open

在文件 proc_file.c 第 663 行定义.

{
    int result = 0;
 
    if (pde == NULL) {
        return -EPERM;
    }
    pde->pf->fPos = 0;
    atomic_set(&pde->count, 1);
    if (S_ISDIR(pde->mode)) {
        pde->pdirCurrent = pde->subdir;
    }
 
    if ((pde->procFileOps != NULL) && (pde->procFileOps->release != NULL)) {
        result = pde->procFileOps->release((struct Vnode *)pde, pde->pf);
    }
    LosBufRelease(pde->pf->sbuf);
    pde->pf->sbuf = NULL;
 
    if (pde->parent == NULL) {
        FreeProcEntry(pde);
    }
    return result;
}

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CreateProcEntry()

struct ProcDirEntry * CreateProcEntry	(	const char *	name,
		mode_t	mode,
		struct ProcDirEntry *	parent
	)

创建 pro (目录/文件)项

create a proc node

在文件 proc_file.c 第 364 行定义.

{
    struct ProcDirEntry *pde = NULL;
 
    if (S_ISDIR(mode)) {//目录模式 0
        pde = ProcCreateDir(parent, name, NULL, mode);//无驱动程序
    } else {
        pde = ProcCreateFile(parent, name, NULL, mode);//无驱动程序
    }
    return pde;
}

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DEFINE_SPINLOCK()

DEFINE_SPINLOCK

(

procfsLock

)

FreeProcEntry()

static void FreeProcEntry ( struct ProcDirEntry *  entry )

static

释放proc

在文件 proc_file.c 第 376 行定义.

{
    if (entry == NULL) {
        return;
    }
    if (entry->pf != NULL) {
        free(entry->pf);
        entry->pf = NULL;
    }
    free(entry);
}

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GetNextDir()

static int GetNextDir ( struct ProcDirEntry *  pn, void *  buf, size_t  len  )

static

在文件 proc_file.c 第 484 行定义.

{
    char *buff = (char *)buf;
 
    if (pn->pdirCurrent == NULL) {
        *buff = '\0';
        return -ENOENT;
    }
    int namelen = pn->pdirCurrent->nameLen;
    int ret = memcpy_s(buff, len, pn->pdirCurrent->name, namelen);
    if (ret != EOK) {
        return -ENAMETOOLONG;
    }
 
    pn->pdirCurrent = pn->pdirCurrent->next;
    pn->pf->fPos++;
    return ENOERR;
}

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GetProcRootEntry()

struct ProcDirEntry * GetProcRootEntry

(

void

)

在文件 proc_file.c 第 688 行定义.

{
    return &g_procRootDirEntry;
}

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LseekDirProcFile()

int LseekDirProcFile	(	struct ProcDirEntry *	pde,
		off_t *	pos,
		int	whence
	)

directory migration

Description:

This API is used to set the proc directory migration

注意

• Only allow SEEK_SET to zero.

参数

pde	[IN] Type #struct ProcDirEntry * pointer of the node structure to be deviated
pos	[IN] Type #off_t * the number of deviation
whence	[IN] Type int the begin of deviation

返回值

#EINVAL	deviation failed
#ENOERR	deviation successfully

Dependency:

• proc_fs.h: the header file that contains the API declaration.

参见

proc_open

在文件 proc_file.c 第 652 行定义.

{
    /* Only allow SEEK_SET to zero */
    if ((whence != SEEK_SET) || (*pos != 0)) {
        return EINVAL;
    }
    pde->pdirCurrent = pde->subdir;
    pde->pf->fPos = 0;
    return ENOERR;
}

LseekProcFile()

loff_t LseekProcFile	(	struct ProcDirEntry *	pde,
		loff_t	offset,
		int	whence
	)

seek proc 文件

File migration

在文件 proc_file.c 第 622 行定义.

{
    if (pde == NULL || pde->pf == NULL) {
        return PROC_ERROR;
    }
 
    struct ProcFile *procFile = pde->pf;
 
    loff_t result = -EINVAL;
 
    switch (whence) {
        case SEEK_CUR:
            result = procFile->fPos + offset;
            break;
 
        case SEEK_SET:
            result = offset;
            break;
 
        default:
            break;
    }
 
    if (result >= 0) {
        procFile->fPos = result;
    }
 
    return result;
}

OpenProcFile()

struct ProcDirEntry * OpenProcFile	(	const char *	fileName,
		int	flags,
			...
	)

open a proc node

Description:

This API is used to open the node by 'fileName' and flags,

注意

• None.

参数

fileName	[IN] Type #const char * the fileName of the node to be opened
flags	[IN] Type int the flags of open's node

返回值

#NULL	open failed
#NOT	NULL open successfully

Dependency:

• proc_fs.h: the header file that contains the API declaration.

参见

proc_close

在文件 proc_file.c 第 553 行定义.

{
    unsigned int intSave;
    struct ProcDirEntry *pn = ProcFindEntry(fileName);
    if (pn == NULL) {
        return NULL;
    }
 
    SCHEDULER_LOCK(intSave);
    if (S_ISREG(pn->mode) && (pn->count != 1)) {
        SCHEDULER_UNLOCK(intSave);
        return NULL;
    }
 
    pn->flags = (unsigned int)(pn->flags) | (unsigned int)flags;
    atomic_set(&pn->count, PROC_INUSE);
    SCHEDULER_UNLOCK(intSave);
    if (ProcOpen(pn->pf) != OK) {
        return NULL;
    }
    if (S_ISREG(pn->mode) && (pn->procFileOps != NULL) && (pn->procFileOps->open != NULL)) {
        (void)pn->procFileOps->open((struct Vnode *)pn, pn->pf);
    }
    if (S_ISDIR(pn->mode)) {
        pn->pdirCurrent = pn->subdir;
        pn->pf->fPos = 0;
    }
 
    return pn;
}

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ProcAddNode()

static int ProcAddNode ( struct ProcDirEntry *  parent, struct ProcDirEntry *  pn  )

static

在文件 proc_file.c 第 261 行定义.

{
    struct ProcDirEntry *temp = NULL;
 
    if (parent == NULL) {
        PRINT_ERR("%s(): parent is NULL", __FUNCTION__);
        return -EINVAL;
    }
 
    if (pn->parent != NULL) {
        PRINT_ERR("%s(): node already has a parent", __FUNCTION__);
        return -EINVAL;
    }
 
    if (S_ISDIR(parent->mode) == 0) {
        PRINT_ERR("%s(): parent is not a directory", __FUNCTION__);
        return -EINVAL;
    }
 
    spin_lock(&procfsLock);
 
    temp = ProcFindNode(parent, pn->name);
    if (temp != NULL) {
        PRINT_ERR("Error!ProcDirEntry '%s/%s' already registered\n", parent->name, pn->name);
        spin_unlock(&procfsLock);
        return -EEXIST;
    }
 
    pn->parent = parent;
    pn->next = parent->subdir;
    parent->subdir = pn;
 
    spin_unlock(&procfsLock);
 
    return 0;
}

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ProcAllocNode()

static struct ProcDirEntry * ProcAllocNode ( struct ProcDirEntry **  parent, const char *  name, mode_t  mode  )

static

分配 proc 节点

在文件 proc_file.c 第 202 行定义.

{
    struct ProcDirEntry *pn = NULL;
    const char *lastName = NULL;
    int ret;
 
    if ((name == NULL) || (strlen(name) == 0) || (procfsInit == false)) {
        return pn;
    }
 
    if (CheckProcName(name, parent, &lastName) != 0) {
        return pn;
    }
 
    if (strlen(lastName) > NAME_MAX) {
        return pn;
    }
 
    if ((S_ISDIR((*parent)->mode) == 0) || (strchr(lastName, '/'))) {
        return pn;
    }
    //开始各种造初始数据
    pn = (struct ProcDirEntry *)malloc(sizeof(struct ProcDirEntry));//从内核分配内存
    if (pn == NULL) {
        return NULL;
    }
 
    if ((mode & S_IALLUGO) == 0) {
        mode |= S_IRUSR | S_IRGRP | S_IROTH;
    }
 
    (void)memset_s(pn, sizeof(struct ProcDirEntry), 0, sizeof(struct ProcDirEntry));//初始化内存
    pn->nameLen = strlen(lastName);
    pn->mode = mode;
    ret = memcpy_s(pn->name, sizeof(pn->name), lastName, strlen(lastName) + 1);
    if (ret != EOK) {
        free(pn);
        return NULL;
    }
 
    pn->pf = (struct ProcFile *)malloc(sizeof(struct ProcFile));
    if (pn->pf == NULL) {
        free(pn);
        return NULL;
    }
    (void)memset_s(pn->pf, sizeof(struct ProcFile), 0, sizeof(struct ProcFile));
    pn->pf->pPDE = pn;
    ret = memcpy_s(pn->pf->name, sizeof(pn->pf->name), pn->name, pn->nameLen + 1);
    if (ret != EOK) {
        free(pn->pf);
        free(pn);
        return NULL;
    }
 
    atomic_set(&pn->count, 1);//默认有一个引用
    spin_lock_init(&pn->pdeUnloadLock);
    return pn;
}

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ProcCreate()

struct ProcDirEntry * ProcCreate	(	const char *	name,
		mode_t	mode,
		struct ProcDirEntry *	parent,
		const struct ProcFileOperations *	procFops
	)

create a proc node

Description:

This API is used to create the node by 'name' and parent vnode, And assignment operation function

注意

• This interface should be called after system initialization.
• The parameter name should be a valid string.

参数

name	[IN] Type #const char * The name of the node to be created.
mode	[IN] Type mode_t the mode of create's node.
parent	[IN] Type #struct ProcDirEntry * the parent node of the node to be created.
procFops	[IN] Type #const struct ProcFileOperations * operation function of the node.

返回值

#NULL	Create failed.
#ProcDirEntry*	Create successfully.

Dependency:

• proc_fs.h: the header file that contains the API declaration.

参见

在文件 proc_file.c 第 457 行定义.

{
    return ProcCreateData(name, mode, parent, procFileOps, NULL);
}

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ProcCreateData()

struct ProcDirEntry * ProcCreateData	(	const char *	name,
		mode_t	mode,
		struct ProcDirEntry *	parent,
		const struct ProcFileOperations *	procFileOps,
		void *	data
	)

创建数据

在文件 proc_file.c 第 444 行定义.

{
    struct ProcDirEntry *pde = CreateProcEntry(name, mode, parent);
    if (pde != NULL) {
        if (procFileOps != NULL) {
            pde->procFileOps = procFileOps;
        }
        pde->data = data;
    }
    return pde;
}

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ProcCreateDir()

static struct ProcDirEntry * ProcCreateDir ( struct ProcDirEntry *  parent, const char *  name, const struct ProcFileOperations *  procFileOps, mode_t  mode  )

static

/proc文件系统创建目录的方式

在文件 proc_file.c 第 319 行定义.

{
    struct ProcDirEntry *pn = NULL;
    int ret;
 
    pn = ProcAllocNode(&parent, name, S_IFDIR | mode);//1.先创造一个数据项 ProcDirEntry
    if (pn == NULL) {
        return pn;
    }
    pn->procFileOps = procFileOps;//绑定数据项的文件系统
    pn->type = VNODE_TYPE_DIR;
    ret = ProcAddNode(parent, pn);
    if (ret != 0) {
        free(pn->pf);
        free(pn);
        return NULL;
    }
 
    return pn;
}

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ProcCreateFile()

static struct ProcDirEntry * ProcCreateFile ( struct ProcDirEntry *  parent, const char *  name, const struct ProcFileOperations *  procFileOps, mode_t  mode  )

static

创建文件项

在文件 proc_file.c 第 341 行定义.

{
    struct ProcDirEntry *pn = NULL;
    int ret;
 
    pn = ProcAllocNode(&parent, name, S_IFREG | mode);//分配一个节点,S_IFREG代表是文件类型
    if (pn == NULL) {
        return pn;
    }
 
    pn->procFileOps = procFileOps;//驱动程序
    pn->type = VNODE_TYPE_REG;  //文件类型
    ret = ProcAddNode(parent, pn);
    if (ret != 0) {
        free(pn->pf);
        free(pn);
        return NULL;
    }
 
    return pn;
}

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ProcDetachNode()

static void ProcDetachNode ( struct ProcDirEntry *  pn )

static

在文件 proc_file.c 第 298 行定义.

{
    struct ProcDirEntry *parent = pn->parent;
    struct ProcDirEntry **iter = NULL;
 
    if (parent == NULL) {
        PRINT_ERR("%s(): node has no parent", __FUNCTION__);
        return;
    }
 
    iter = &parent->subdir;
    while (*iter != NULL) {
        if (*iter == pn) {
            *iter = pn->next;
            break;
        }
        iter = &(*iter)->next;
    }
    pn->parent = NULL;
}

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ProcFindEntry()

struct ProcDirEntry * ProcFindEntry

(

const char *

path

)

在文件 proc_file.c 第 95 行定义.

{
    struct ProcDirEntry *pn = NULL;
    int isfoundsub;
    const char *next = NULL;
    unsigned int len;
    int leveltotal = 0;
    int levelcount = 0;
    const char *p = NULL;
    const char *name = path;
 
    while ((p = strchr(name, '/')) != NULL) {
        leveltotal++;
        name = p;
        name++;
    }
    if (leveltotal < 1) {
        return pn;
    }
 
    spin_lock(&procfsLock);
 
    pn = &g_procRootDirEntry;
 
    while ((pn != NULL) && (levelcount < leveltotal)) {
        levelcount++;
        isfoundsub = 0;
        while (pn != NULL) {
            next = strchr(path, '/');
            if (next == NULL) {
                while (pn != NULL) {
                    if (strcmp(path, pn->name) == 0) {
                        spin_unlock(&procfsLock);
                        return pn;
                    }
                    pn = pn->next;
                }
                pn = NULL;
                spin_unlock(&procfsLock);
                return pn;
            }
 
            len = next - path;
            if (pn == &g_procRootDirEntry) {
                if (levelcount == leveltotal) {
                    spin_unlock(&procfsLock);
                    return pn;
                }
                len = g_procRootDirEntry.nameLen;
            }
            if (ProcMatch(len, path, pn)) {
                isfoundsub = 1;
                path += len + 1;
                break;
            }
 
            pn = pn->next;
        }
 
        if ((isfoundsub == 1) && (pn != NULL)) {
            pn = pn->subdir;
        } else {
            pn = NULL;
            spin_unlock(&procfsLock);
            return pn;
        }
    }
    spin_unlock(&procfsLock);
    return NULL;
}

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ProcFindNode()

static struct ProcDirEntry * ProcFindNode ( struct ProcDirEntry *  parent, const char *  name  )

static

在文件 proc_file.c 第 70 行定义.

{
    struct ProcDirEntry *pn = NULL;
    int length;
 
    if ((parent == NULL) || (name == NULL)) {
        return pn;
    }
    length = strlen(name);
 
    for (pn = parent->subdir; pn != NULL; pn = pn->next) {
        if ((length == pn->nameLen) && strcmp(pn->name, name) == 0) {
            break;
        }
    }
 
    return pn;
}

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ProcFreeEntry()

void ProcFreeEntry

(

struct ProcDirEntry *

pn

)

释放

在文件 proc_file.c 第 388 行定义.

{
    if (atomic_dec_and_test(&pn->count))
        FreeProcEntry(pn);
}

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ProcMatch()

int ProcMatch	(	unsigned int	len,
		const char *	name,
		struct ProcDirEntry *	pn
	)

在文件 proc_file.c 第 63 行定义.

{
    if (len != pn->nameLen)
        return 0;
    return !strncmp(name, pn->name, len);
}

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ProcMkdir()

struct ProcDirEntry * ProcMkdir	(	const char *	name,
		struct ProcDirEntry *	parent
	)

create a proc directory node

Description:

This API is used to create the directory node by 'name' and parent vnode

注意

• This interface should be called after system initialization.
• The parameter name should be a valid string.

参数

name	[IN] Type #const char * The name of the node directory to be created.
parent	[IN] Type #struct ProcDirEntry * the parent node of the directory node to be created, if pass NULL, default parent node is "/proc".

返回值

#NULL	Create failed.
#ProcDirEntry*	Create successfully.

Dependency:

• proc_fs.h: the header file that contains the API declaration.

参见

在文件 proc_file.c 第 439 行定义.

{
    return ProcCreateDir(parent, name, NULL, 0);
}

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ProcMkdirMode()

struct ProcDirEntry * ProcMkdirMode	(	const char *	name,
		mode_t	mode,
		struct ProcDirEntry *	parent
	)

在文件 proc_file.c 第 434 行定义.

{
    return ProcCreateDir(parent, name, NULL, mode);
}

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ProcOpen()

int ProcOpen

(

struct ProcFile *

procFile

)

打开 pro

在文件 proc_file.c 第 503 行定义.

{
    if (procFile == NULL) {
        return PROC_ERROR;
    }
    if (procFile->sbuf != NULL) {
        return OK;
    }
 
    struct SeqBuf *buf = LosBufCreat();//创建一个 seq buf
    if (buf == NULL) {
        return PROC_ERROR;
    }
    procFile->sbuf = buf;
    return OK;
}

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ProcRead()

static int ProcRead ( struct ProcDirEntry *  pde, char *  buf, size_t  len  )

static

在文件 proc_file.c 第 520 行定义.

{
    if (pde == NULL || pde->pf == NULL) {
        return PROC_ERROR;
    }
    struct ProcFile *procFile = pde->pf;
    struct SeqBuf *sb = procFile->sbuf;
 
    if (sb->buf == NULL) {
        // only read once to build the storage buffer
        if (pde->procFileOps->read(sb, NULL) != 0) {
            return PROC_ERROR;
        }
    }
 
    size_t realLen;
    loff_t pos = procFile->fPos;
 
    if ((pos >= sb->count) || (len == 0)) {
        /* there's no data or at the file tail. */
        realLen = 0;
    } else {
        realLen = MIN((sb->count - pos), MIN(len, INT_MAX));
        if (LOS_CopyFromKernel(buf, len, sb->buf + pos, realLen) != 0) {
            return PROC_ERROR;
        }
 
        procFile->fPos = pos + realLen;
    }
 
    return (ssize_t)realLen;
}

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ProcStat()

int ProcStat	(	const char *	file,
		struct ProcStat *	buf
	)

在文件 proc_file.c 第 463 行定义.

{
    struct ProcDirEntry *pn = NULL;
    int len = sizeof(buf->name);
    int ret;
 
    pn = ProcFindEntry(file);
    if (pn == NULL) {
        return ENOENT;
    }
    ret = strncpy_s(buf->name, len, pn->name, len - 1);
    if (ret != EOK) {
        return ENAMETOOLONG;
    }
    buf->name[len - 1] = '\0';
    buf->stMode = pn->mode;
    buf->pPDE = pn;
 
    return 0;
}

函数调用图:

ReadProcFile()

int ReadProcFile	(	struct ProcDirEntry *	pde,
		void *	buf,
		size_t	len
	)

read a proc node

Description:

This API is used to read the node by pde

注意

• None.

参数

pde	[IN] Type #struct ProcDirEntry * pointer of the node structure to be read
buf	[IN] Type void * user-provided to save the data
len	[IN] Type size_t the length of want to read

返回值

#-1	read failed
#>0	Number of bytes read success

Dependency:

• proc_fs.h: the header file that contains the API declaration.

参见

proc_open

在文件 proc_file.c 第 584 行定义.

{
    int result = -EPERM;
 
    if (pde == NULL) {
        return result;
    }
    if (S_ISREG(pde->mode)) {
        if ((pde->procFileOps != NULL) && (pde->procFileOps->read != NULL)) {
            result = ProcRead(pde, (char *)buf, len);
        }
    } else if (S_ISDIR(pde->mode)) {
        result = GetNextDir(pde, buf, len);
    }
    return result;
}

函数调用图:

这是这个函数的调用关系图:

RemoveProcEntry()

void RemoveProcEntry	(	const char *	name,
		struct ProcDirEntry *	parent
	)

remove a proc node

Description:

This API is used to remove the node by 'name' and parent vnode

注意

• This interface should be called after system initialization.
• The parameter name should be a valid string.

参数

name	[IN] Type #const char * The name of the node to be removed.
parent	[IN] Type #struct ProcDirEntry * the parent node of the node to be remove.

Dependency:

• proc_fs.h: the header file that contains the API declaration.

参见

在文件 proc_file.c 第 405 行定义.

{
    struct ProcDirEntry *pn = NULL;
    const char *lastName = name;
 
    if ((name == NULL) || (strlen(name) == 0) || (procfsInit == false)) {
        return;
    }
 
    if (CheckProcName(name, &parent, &lastName) != 0) {
        return;
    }
 
    spin_lock(&procfsLock);
 
    pn = ProcFindNode(parent, lastName);
    if (pn == NULL) {
        PRINT_ERR("Error:name '%s' not found!\n", name);
        spin_unlock(&procfsLock);
        return;
    }
    ProcDetachNode(pn);
 
    spin_unlock(&procfsLock);
 
    RemoveProcEntryTravalsal(pn->subdir);
    ProcFreeEntry(pn);
}

函数调用图:

RemoveProcEntryTravalsal()

static void RemoveProcEntryTravalsal ( struct ProcDirEntry *  pn )

static

在文件 proc_file.c 第 394 行定义.

{
    if (pn == NULL) {
        return;
    }
    RemoveProcEntryTravalsal(pn->next);
    RemoveProcEntryTravalsal(pn->subdir);
 
    ProcFreeEntry(pn);
}

函数调用图:

这是这个函数的调用关系图:

WriteProcFile()

int WriteProcFile	(	struct ProcDirEntry *	pde,
		const void *	buf,
		size_t	len
	)

写 proc 文件

write a proc node

在文件 proc_file.c 第 601 行定义.

{
    int result = -EPERM;
 
    if (pde == NULL) {
        return result;
    }
 
    if (S_ISDIR(pde->mode)) {
        return -EISDIR;
    }
 
    spin_lock(&procfsLock);
    if ((pde->procFileOps != NULL) && (pde->procFileOps->write != NULL)) {
        result = pde->procFileOps->write(pde->pf, (const char *)buf, len, &(pde->pf->fPos));
    }
    spin_unlock(&procfsLock);
 
    return result;
}

这是这个函数的调用关系图:

变量说明

g_procPf

struct ProcFile g_procPf

static

初始值:

= {
    .fPos       = 0,
}

在文件 proc_file.c 第 46 行定义.

g_procRootDirEntry

struct ProcDirEntry g_procRootDirEntry

static

初始值:

= { 
    .nameLen     = 5,
    .mode        = S_IFDIR | PROCFS_DEFAULT_MODE,
    .count       = ATOMIC_INIT(1),
    .procFileOps = NULL,
    .parent      = &g_procRootDirEntry,
    .name        = "/proc", 
    .subdir      = NULL,    
    .next        = NULL,    
    .pf          = &g_procPf,       
    .type        = VNODE_TYPE_DIR,  
}

在文件 proc_file.c 第 50 行定义.

procfsInit

bool procfsInit = false

在文件 proc_file.c 第 44 行定义.