// Copyright 2015-2017 Espressif Systems (Shanghai) PTE LTD // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. #include #include #include #include #include #include #include #include #include #include "esp_vfs.h" #include "esp_log.h" #include "port/arch/sys_arch.h" #include "lwip/sys.h" #define VFS_MAX_COUNT 8 /* max number of VFS entries (registered filesystems) */ #define MIN_LWIP_FD (FD_SETSIZE - CONFIG_LWIP_MAX_SOCKETS) #define LEN_PATH_PREFIX_IGNORED SIZE_MAX /* special length value for VFS which is never recognised by open() */ typedef struct vfs_entry_ { esp_vfs_t vfs; // contains pointers to VFS functions char path_prefix[ESP_VFS_PATH_MAX]; // path prefix mapped to this VFS size_t path_prefix_len; // micro-optimization to avoid doing extra strlen void* ctx; // optional pointer which can be passed to VFS int offset; // index of this structure in s_vfs array } vfs_entry_t; typedef struct { bool isset; // none or at least one bit is set in the following 3 fd sets fd_set readfds; fd_set writefds; fd_set errorfds; } fds_triple_t; static vfs_entry_t* s_vfs[VFS_MAX_COUNT] = { 0 }; static size_t s_vfs_count = 0; static short fd_vfs[FD_SETSIZE] = { [0 ... FD_SETSIZE-1] = -1 }; static esp_err_t esp_vfs_register_common(const char* base_path, size_t len, const esp_vfs_t* vfs, void* ctx, int *vfs_entry_index) { if (len != LEN_PATH_PREFIX_IGNORED) { if ((len != 0 && len < 2) || (len > ESP_VFS_PATH_MAX)) { return ESP_ERR_INVALID_ARG; } if ((len > 0 && base_path[0] != '/') || base_path[len - 1] == '/') { return ESP_ERR_INVALID_ARG; } } vfs_entry_t *entry = (vfs_entry_t*) malloc(sizeof(vfs_entry_t)); if (entry == NULL) { return ESP_ERR_NO_MEM; } size_t index; for (index = 0; index < s_vfs_count; ++index) { if (s_vfs[index] == NULL) { break; } } if (index == s_vfs_count) { if (s_vfs_count >= VFS_MAX_COUNT) { free(entry); return ESP_ERR_NO_MEM; } ++s_vfs_count; } s_vfs[index] = entry; if (len != LEN_PATH_PREFIX_IGNORED) { strcpy(entry->path_prefix, base_path); // we have already verified argument length } else { bzero(entry->path_prefix, sizeof(entry->path_prefix)); } memcpy(&entry->vfs, vfs, sizeof(esp_vfs_t)); entry->path_prefix_len = len; entry->ctx = ctx; entry->offset = index; if (vfs_entry_index) { *vfs_entry_index = index; } return ESP_OK; } esp_err_t esp_vfs_register(const char* base_path, const esp_vfs_t* vfs, void* ctx) { return esp_vfs_register_common(base_path, strlen(base_path), vfs, ctx, NULL); } esp_err_t esp_vfs_register_socket_space(const esp_vfs_t *vfs, void *ctx, int *p_min_fd, int *p_max_fd) { int index = -1; esp_err_t ret = esp_vfs_register_common("", LEN_PATH_PREFIX_IGNORED, vfs, ctx, &index); if (ret == ESP_OK) { if (p_min_fd != NULL) { *p_min_fd = MIN_LWIP_FD; } if (p_max_fd != NULL) { *p_max_fd = FD_SETSIZE; } } for (int i = MIN_LWIP_FD; i < FD_SETSIZE; ++i) { fd_vfs[i] = index; } return ret; } esp_err_t esp_vfs_unregister(const char* base_path) { for (size_t i = 0; i < s_vfs_count; ++i) { vfs_entry_t* vfs = s_vfs[i]; if (vfs == NULL) { continue; } if (memcmp(base_path, vfs->path_prefix, vfs->path_prefix_len) == 0) { free(vfs); s_vfs[i] = NULL; // Delete all references from the FD lookup-table for (int j = 0; j < FD_SETSIZE; ++j) { if (fd_vfs[j] == i) { fd_vfs[j] = -1; } } return ESP_OK; } } return ESP_ERR_INVALID_STATE; } static inline const vfs_entry_t* get_vfs_for_index(int index) { if (index < 0 || index >= s_vfs_count) { return NULL; } else { return s_vfs[index]; } } static inline bool fd_valid(int fd) { return (fd < FD_SETSIZE) && (fd >= 0); } static inline const vfs_entry_t* get_vfs_for_fd(int fd) { if (fd_valid(fd)) { return get_vfs_for_index(fd_vfs[fd]); } else { return NULL; } } static const char* translate_path(const vfs_entry_t* vfs, const char* src_path) { assert(strncmp(src_path, vfs->path_prefix, vfs->path_prefix_len) == 0); if (strlen(src_path) == vfs->path_prefix_len) { // special case when src_path matches the path prefix exactly return "/"; } return src_path + vfs->path_prefix_len; } static const vfs_entry_t* get_vfs_for_path(const char* path) { const vfs_entry_t* best_match = NULL; ssize_t best_match_prefix_len = -1; size_t len = strlen(path); for (size_t i = 0; i < s_vfs_count; ++i) { const vfs_entry_t* vfs = s_vfs[i]; if (!vfs || vfs->path_prefix_len == LEN_PATH_PREFIX_IGNORED) { continue; } // match path prefix if (len < vfs->path_prefix_len || memcmp(path, vfs->path_prefix, vfs->path_prefix_len) != 0) { continue; } // this is the default VFS and we don't have a better match yet. if (vfs->path_prefix_len == 0 && !best_match) { best_match = vfs; continue; } // if path is not equal to the prefix, expect to see a path separator // i.e. don't match "/data" prefix for "/data1/foo.txt" path if (len > vfs->path_prefix_len && path[vfs->path_prefix_len] != '/') { continue; } // Out of all matching path prefixes, select the longest one; // i.e. if "/dev" and "/dev/uart" both match, for "/dev/uart/1" path, // choose "/dev/uart", // This causes all s_vfs_count VFS entries to be scanned when opening // a file by name. This can be optimized by introducing a table for // FS search order, sorted so that longer prefixes are checked first. if (best_match_prefix_len < (ssize_t) vfs->path_prefix_len) { best_match_prefix_len = (ssize_t) vfs->path_prefix_len; best_match = vfs; } } return best_match; } /* * Using huge multi-line macros is never nice, but in this case * the only alternative is to repeat this chunk of code (with different function names) * for each syscall being implemented. Given that this define is contained within a single * file, this looks like a good tradeoff. * * First we check if syscall is implemented by VFS (corresponding member is not NULL), * then call the right flavor of the method (e.g. open or open_p) depending on * ESP_VFS_FLAG_CONTEXT_PTR flag. If ESP_VFS_FLAG_CONTEXT_PTR is set, context is passed * in as first argument and _p variant is used for the call. * It is enough to check just one of them for NULL, as both variants are part of a union. */ #define CHECK_AND_CALL(ret, r, pvfs, func, ...) \ if (pvfs->vfs.func == NULL) { \ __errno_r(r) = ENOSYS; \ return -1; \ } \ if (pvfs->vfs.flags & ESP_VFS_FLAG_CONTEXT_PTR) { \ ret = (*pvfs->vfs.func ## _p)(pvfs->ctx, __VA_ARGS__); \ } else { \ ret = (*pvfs->vfs.func)(__VA_ARGS__);\ } #define CHECK_AND_CALLV(r, pvfs, func, ...) \ if (pvfs->vfs.func == NULL) { \ __errno_r(r) = ENOSYS; \ return; \ } \ if (pvfs->vfs.flags & ESP_VFS_FLAG_CONTEXT_PTR) { \ (*pvfs->vfs.func ## _p)(pvfs->ctx, __VA_ARGS__); \ } else { \ (*pvfs->vfs.func)(__VA_ARGS__);\ } #define CHECK_AND_CALLP(ret, r, pvfs, func, ...) \ if (pvfs->vfs.func == NULL) { \ __errno_r(r) = ENOSYS; \ return NULL; \ } \ if (pvfs->vfs.flags & ESP_VFS_FLAG_CONTEXT_PTR) { \ ret = (*pvfs->vfs.func ## _p)(pvfs->ctx, __VA_ARGS__); \ } else { \ ret = (*pvfs->vfs.func)(__VA_ARGS__);\ } int esp_vfs_open(struct _reent *r, const char * path, int flags, int mode) { const vfs_entry_t* vfs = get_vfs_for_path(path); if (vfs == NULL) { __errno_r(r) = ENOENT; return -1; } const char* path_within_vfs = translate_path(vfs, path); int ret; CHECK_AND_CALL(ret, r, vfs, open, path_within_vfs, flags, mode); if (ret >= MIN_LWIP_FD) { CHECK_AND_CALL(ret, r, vfs, close, ret); __errno_r(r) = ENFILE; return -1; } if (ret >= 0) { fd_vfs[ret] = vfs->offset; } return ret; } ssize_t esp_vfs_write(struct _reent *r, int fd, const void * data, size_t size) { const vfs_entry_t* vfs = get_vfs_for_fd(fd); if (vfs == NULL) { __errno_r(r) = EBADF; return -1; } ssize_t ret; CHECK_AND_CALL(ret, r, vfs, write, fd, data, size); return ret; } off_t esp_vfs_lseek(struct _reent *r, int fd, off_t size, int mode) { const vfs_entry_t* vfs = get_vfs_for_fd(fd); if (vfs == NULL) { __errno_r(r) = EBADF; return -1; } off_t ret; CHECK_AND_CALL(ret, r, vfs, lseek, fd, size, mode); return ret; } ssize_t esp_vfs_read(struct _reent *r, int fd, void * dst, size_t size) { const vfs_entry_t* vfs = get_vfs_for_fd(fd); if (vfs == NULL) { __errno_r(r) = EBADF; return -1; } ssize_t ret; CHECK_AND_CALL(ret, r, vfs, read, fd, dst, size); return ret; } int esp_vfs_close(struct _reent *r, int fd) { const vfs_entry_t* vfs = get_vfs_for_fd(fd); if (vfs == NULL) { __errno_r(r) = EBADF; return -1; } int ret; CHECK_AND_CALL(ret, r, vfs, close, fd); if (fd < MIN_LWIP_FD) { fd_vfs[fd] = -1; } // else { Leave alone socket FDs because sockets are not created by // esp_vfs_open and therefore fd_vfs won't be set again. //} return ret; } int esp_vfs_fstat(struct _reent *r, int fd, struct stat * st) { const vfs_entry_t* vfs = get_vfs_for_fd(fd); if (vfs == NULL) { __errno_r(r) = EBADF; return -1; } int ret; CHECK_AND_CALL(ret, r, vfs, fstat, fd, st); return ret; } int esp_vfs_stat(struct _reent *r, const char * path, struct stat * st) { const vfs_entry_t* vfs = get_vfs_for_path(path); if (vfs == NULL) { __errno_r(r) = ENOENT; return -1; } const char* path_within_vfs = translate_path(vfs, path); int ret; CHECK_AND_CALL(ret, r, vfs, stat, path_within_vfs, st); return ret; } int esp_vfs_link(struct _reent *r, const char* n1, const char* n2) { const vfs_entry_t* vfs = get_vfs_for_path(n1); if (vfs == NULL) { __errno_r(r) = ENOENT; return -1; } const vfs_entry_t* vfs2 = get_vfs_for_path(n2); if (vfs != vfs2) { __errno_r(r) = EXDEV; return -1; } const char* path1_within_vfs = translate_path(vfs, n1); const char* path2_within_vfs = translate_path(vfs, n2); int ret; CHECK_AND_CALL(ret, r, vfs, link, path1_within_vfs, path2_within_vfs); return ret; } int esp_vfs_unlink(struct _reent *r, const char *path) { const vfs_entry_t* vfs = get_vfs_for_path(path); if (vfs == NULL) { __errno_r(r) = ENOENT; return -1; } const char* path_within_vfs = translate_path(vfs, path); int ret; CHECK_AND_CALL(ret, r, vfs, unlink, path_within_vfs); return ret; } int esp_vfs_rename(struct _reent *r, const char *src, const char *dst) { const vfs_entry_t* vfs = get_vfs_for_path(src); if (vfs == NULL) { __errno_r(r) = ENOENT; return -1; } const vfs_entry_t* vfs_dst = get_vfs_for_path(dst); if (vfs != vfs_dst) { __errno_r(r) = EXDEV; return -1; } const char* src_within_vfs = translate_path(vfs, src); const char* dst_within_vfs = translate_path(vfs, dst); int ret; CHECK_AND_CALL(ret, r, vfs, rename, src_within_vfs, dst_within_vfs); return ret; } DIR* opendir(const char* name) { const vfs_entry_t* vfs = get_vfs_for_path(name); struct _reent* r = __getreent(); if (vfs == NULL) { __errno_r(r) = ENOENT; return NULL; } const char* path_within_vfs = translate_path(vfs, name); DIR* ret; CHECK_AND_CALLP(ret, r, vfs, opendir, path_within_vfs); if (ret != NULL) { ret->dd_vfs_idx = vfs->offset; } return ret; } struct dirent* readdir(DIR* pdir) { const vfs_entry_t* vfs = get_vfs_for_index(pdir->dd_vfs_idx); struct _reent* r = __getreent(); if (vfs == NULL) { __errno_r(r) = EBADF; return NULL; } struct dirent* ret; CHECK_AND_CALLP(ret, r, vfs, readdir, pdir); return ret; } int readdir_r(DIR* pdir, struct dirent* entry, struct dirent** out_dirent) { const vfs_entry_t* vfs = get_vfs_for_index(pdir->dd_vfs_idx); struct _reent* r = __getreent(); if (vfs == NULL) { errno = EBADF; return -1; } int ret; CHECK_AND_CALL(ret, r, vfs, readdir_r, pdir, entry, out_dirent); return ret; } long telldir(DIR* pdir) { const vfs_entry_t* vfs = get_vfs_for_index(pdir->dd_vfs_idx); struct _reent* r = __getreent(); if (vfs == NULL) { errno = EBADF; return -1; } long ret; CHECK_AND_CALL(ret, r, vfs, telldir, pdir); return ret; } void seekdir(DIR* pdir, long loc) { const vfs_entry_t* vfs = get_vfs_for_index(pdir->dd_vfs_idx); struct _reent* r = __getreent(); if (vfs == NULL) { errno = EBADF; return; } CHECK_AND_CALLV(r, vfs, seekdir, pdir, loc); } void rewinddir(DIR* pdir) { seekdir(pdir, 0); } int closedir(DIR* pdir) { const vfs_entry_t* vfs = get_vfs_for_index(pdir->dd_vfs_idx); struct _reent* r = __getreent(); if (vfs == NULL) { errno = EBADF; return -1; } int ret; CHECK_AND_CALL(ret, r, vfs, closedir, pdir); return ret; } int mkdir(const char* name, mode_t mode) { const vfs_entry_t* vfs = get_vfs_for_path(name); struct _reent* r = __getreent(); if (vfs == NULL) { __errno_r(r) = ENOENT; return -1; } const char* path_within_vfs = translate_path(vfs, name); int ret; CHECK_AND_CALL(ret, r, vfs, mkdir, path_within_vfs, mode); return ret; } int rmdir(const char* name) { const vfs_entry_t* vfs = get_vfs_for_path(name); struct _reent* r = __getreent(); if (vfs == NULL) { __errno_r(r) = ENOENT; return -1; } const char* path_within_vfs = translate_path(vfs, name); int ret; CHECK_AND_CALL(ret, r, vfs, rmdir, path_within_vfs); return ret; } int fcntl(int fd, int cmd, ...) { const vfs_entry_t* vfs = get_vfs_for_fd(fd); struct _reent* r = __getreent(); if (vfs == NULL) { __errno_r(r) = EBADF; return -1; } int ret; va_list args; va_start(args, cmd); CHECK_AND_CALL(ret, r, vfs, fcntl, fd, cmd, args); va_end(args); return ret; } int ioctl(int fd, int cmd, ...) { const vfs_entry_t* vfs = get_vfs_for_fd(fd); struct _reent* r = __getreent(); if (vfs == NULL) { __errno_r(r) = EBADF; return -1; } int ret; va_list args; va_start(args, cmd); CHECK_AND_CALL(ret, r, vfs, ioctl, fd, cmd, args); va_end(args); return ret; } int fsync(int fd) { const vfs_entry_t* vfs = get_vfs_for_fd(fd); struct _reent* r = __getreent(); if (vfs == NULL) { __errno_r(r) = EBADF; return -1; } int ret; CHECK_AND_CALL(ret, r, vfs, fsync, fd); return ret; } static void call_end_selects(int end_index, const fds_triple_t *vfs_fds_triple) { for (int i = 0; i < end_index; ++i) { const vfs_entry_t *vfs = get_vfs_for_index(i); const fds_triple_t *item = &vfs_fds_triple[i]; if (vfs && vfs->vfs.end_select && item->isset) { vfs->vfs.end_select(); } } } static int set_global_fd_sets(const fds_triple_t *vfs_fds_triple, int size, fd_set *readfds, fd_set *writefds, fd_set *errorfds) { int ret = 0; for (int i = 0; i < size; ++i) { const fds_triple_t *item = &vfs_fds_triple[i]; if (item->isset) { for (int j = 0; j < sizeof(item->readfds.fds_bits)/sizeof(item->readfds.fds_bits[0]); ++j) { if (readfds != NULL) { readfds->fds_bits[j] |= item->readfds.fds_bits[j]; ret += __builtin_popcountl(item->readfds.fds_bits[j]); } if (writefds != NULL) { writefds->fds_bits[j] |= item->writefds.fds_bits[j]; ret += __builtin_popcountl(item->writefds.fds_bits[j]); } if (errorfds != NULL) { errorfds->fds_bits[j] |= item->errorfds.fds_bits[j]; ret += __builtin_popcountl(item->errorfds.fds_bits[j]); } } } } return ret; } int esp_vfs_select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *errorfds, struct timeval *timeout) { const int non_socket_nfds = MIN(nfds, MIN_LWIP_FD); int ret = 0; struct _reent* r = __getreent(); if (nfds > FD_SETSIZE || nfds < 0) { __errno_r(r) = EINVAL; return -1; } fds_triple_t *vfs_fds_triple; if ((vfs_fds_triple = calloc(s_vfs_count, sizeof(fds_triple_t))) == NULL) { __errno_r(r) = ENOMEM; return -1; } for (int i = 0; i < non_socket_nfds; ++i) { if (fd_vfs[i] < 0) { continue; } fds_triple_t *item = &vfs_fds_triple[fd_vfs[i]]; // FD sets for VFS which belongs to FD i if (readfds && FD_ISSET(i, readfds)) { item->isset = true; FD_SET(i, &item->readfds); FD_CLR(i, readfds); } if (writefds && FD_ISSET(i, writefds)) { item->isset = true; FD_SET(i, &item->writefds); FD_CLR(i, writefds); } if (errorfds && FD_ISSET(i, errorfds)) { item->isset = true; FD_SET(i, &item->errorfds); FD_CLR(i, errorfds); } } // all non-socket VFSs have their FD sets in vfs_fds_triple // the global readfds, writefds and errorfds contain only socket FDs void *callback_handle = sys_thread_sem_get(); if (!callback_handle) { __errno_r(r) = ENOMEM; return -1; } sys_arch_sem_wait(callback_handle, 1); //ensure the semaphore is taken so we are not signalled out-of-sequence; 0 timeout would block forever for (int i = 0; i < s_vfs_count; ++i) { const vfs_entry_t *vfs = get_vfs_for_index(i); fds_triple_t *item = &vfs_fds_triple[i]; if (vfs && vfs->vfs.start_select && item->isset) { // call start_select for all non-socket VFSs with has at least one FD set in readfds, writefds, or errorfds // note: it can point to socket VFS but item->isset will be false for that esp_err_t err = vfs->vfs.start_select(nfds, &item->readfds, &item->writefds, &item->errorfds, callback_handle); if (err != ESP_OK) { call_end_selects(i, vfs_fds_triple); (void) set_global_fd_sets(vfs_fds_triple, s_vfs_count, readfds, writefds, errorfds); free(vfs_fds_triple); __errno_r(r) = ENOMEM; return -1; } } } int socket_select_called = 0; for (int i = MIN_LWIP_FD; i < FD_SETSIZE; ++i) { const vfs_entry_t* vfs = get_vfs_for_fd(i); if (vfs != NULL && vfs->vfs.socket_select != NULL) { // find socket VFS and call socket_select ret = vfs->vfs.socket_select(nfds, readfds, writefds, errorfds, timeout); socket_select_called = 1; break; } } if (!socket_select_called) { uint32_t timeout_ms = 0; if (readfds) { FD_ZERO(readfds); } if (writefds) { FD_ZERO(writefds); } if (errorfds) { FD_ZERO(errorfds); } if (timeout) { timeout_ms = timeout->tv_sec * 1000 + timeout->tv_usec / 1000; timeout_ms = MAX(timeout_ms, 1); //make sure it is not 0 which would be in infinite wait } sys_arch_sem_wait(callback_handle, timeout_ms); sys_sem_free(callback_handle); } call_end_selects(s_vfs_count, vfs_fds_triple); // for VFSs for start_select was called before if (ret >= 0) { ret += set_global_fd_sets(vfs_fds_triple, s_vfs_count, readfds, writefds, errorfds); } //don't free callback_handle because it is freed in lwip_select (vfs.socket_select) free(vfs_fds_triple); return ret; } void esp_vfs_select_triggered(void *callback_handle) { if (callback_handle) { sys_sem_signal(callback_handle); //vfs->vfs.socket_select will return } } void esp_vfs_select_triggered_isr(void *callback_handle, BaseType_t *woken) { if (callback_handle && sys_sem_signal_isr(callback_handle) && woken) { *woken = pdTRUE; } }