diff options
| -rw-r--r-- | core/fs.c | 128 |
1 files changed, 80 insertions, 48 deletions
@@ -11,6 +11,10 @@ struct fs_info *this_fs = NULL; /* Root filesystem */ /* Actual file structures (we don't have malloc yet...) */ struct file files[MAX_OPEN]; +/* Symlink hard limits */ +#define MAX_SYMLINK_CNT 20 +#define MAX_SYMLINK_BUF 4096 + /* * Get a new inode structure */ @@ -92,7 +96,7 @@ void pm_unmangle_name(com32sys_t *regs) { const char *src = MK_PTR(regs->ds, regs->esi.w[0]); char *dst = MK_PTR(regs->es, regs->edi.w[0]); - + dst = unmangle_name(dst, src); /* Update the di register to point to the last null char */ @@ -112,15 +116,15 @@ void getfssec(com32sys_t *regs) char *buf; struct file *file; uint16_t handle; - + sectors = regs->ecx.w[0]; handle = regs->esi.w[0]; file = handle_to_file(handle); - + buf = MK_PTR(regs->es, regs->ebx.w[0]); bytes_read = file->fs->fs_ops->getfssec(file, buf, sectors, &have_more); - + /* * If we reach EOF, the filesystem driver will have already closed * the underlying file... this really should be cleaner. @@ -129,7 +133,7 @@ void getfssec(com32sys_t *regs) _close_file(file); regs->esi.w[0] = 0; } - + regs->ecx.l = bytes_read; } @@ -152,15 +156,13 @@ void pm_searchdir(com32sys_t *regs) int searchdir(const char *name) { - struct inode *inode; - struct inode *parent; + struct inode *inode = NULL; + struct inode *parent = NULL; struct file *file; - char part[256], pathbuf[4096], linkbuf[4096]; - char *p; - int symlink_count = 20; + char *pathbuf = NULL; + char *part, *p, echar; + int symlink_count = MAX_SYMLINK_CNT; - dprintf("Filename: %s\n", name); - if (!(file = alloc_file())) goto err_no_close; file->fs = this_fs; @@ -168,7 +170,7 @@ int searchdir(const char *name) /* if we have ->searchdir method, call it */ if (file->fs->fs_ops->searchdir) { file->fs->fs_ops->searchdir(name, file); - + if (file->open_file) return file_to_handle(file); else @@ -179,66 +181,90 @@ int searchdir(const char *name) /* else, try the generic-path-lookup method */ parent = get_inode(this_fs->cwd); + p = pathbuf = strdup(name); + if (!pathbuf) + goto err; do { got_link: - if (*name == '/') { + if (*p == '/') { put_inode(parent); parent = get_inode(this_fs->root); - while (*name == '/') - name++; } - inode = NULL; + do { + while (*p == '/') + p++; + + if (!*p) + break; + + part = p; + while ((echar = *p) && echar != '/') + p++; + *p++ = '\0'; - while (*name) { - p = part; - while (*name && *name != '/') - *p++ = *name++; - *p = '\0'; if (part[0] != '.' || part[1] != '\0') { inode = this_fs->fs_ops->iget(part, parent); if (!inode) goto err; if (inode->mode == I_SYMLINK) { + char *linkbuf, *q; + int name_len = echar ? strlen(p) : 0; + int total_len = inode->size + name_len + (echar ? 2 : 1); int link_len; - int name_len = strlen(name) + 1; - if (!this_fs->fs_ops->readlink || + if (!this_fs->fs_ops->readlink || --symlink_count == 0 || /* limit check */ - inode->size + name_len >= sizeof linkbuf) + total_len > MAX_SYMLINK_BUF) + goto err; + + linkbuf = malloc(total_len); + if (!linkbuf) goto err; - /* - * Note: we can't generally put this in pathbuf directly, - * because the old "name" may very well be in - * pathbuf already. - */ link_len = this_fs->fs_ops->readlink(inode, linkbuf); - if (link_len <= 0) + if (link_len <= 0) { + free(linkbuf); goto err; - - p = linkbuf + link_len; - if (p[-1] != '/') - *p++ = '/'; - - strlcpy(p, name, sizeof linkbuf - (p-linkbuf)); - - name = strcpy(pathbuf, linkbuf); + } + + q = linkbuf + link_len; + + if (echar) { + if (link_len > 0 && q[-1] != '/') + *q++ = '/'; + + memcpy(q, p, name_len+1); + } else { + *q = '\0'; + } + + free(pathbuf); + p = pathbuf = linkbuf; put_inode(inode); + inode = NULL; goto got_link; } + put_inode(parent); + parent = NULL; + + if (!echar) + break; + + if (inode->mode != I_DIR) + goto err; + parent = inode; + inode = NULL; } - if (!*name) - break; - while (*name == '/') - name++; - } + } while (echar); } while (0); + free(pathbuf); put_inode(parent); + parent = NULL; if (!inode) goto err; @@ -248,8 +274,14 @@ int searchdir(const char *name) file->file_len = inode->size; return file_to_handle(file); - + err: + if (inode) + put_inode(inode); + if (parent) + put_inode(parent); + if (pathbuf) + free(pathbuf); _close_file(file); err_no_close: return -1; @@ -259,7 +291,7 @@ void close_file(com32sys_t *regs) { uint16_t handle = regs->esi.w[0]; struct file *file; - + if (handle) { file = handle_to_file(handle); _close_file(file); @@ -288,10 +320,10 @@ void fs_init(com32sys_t *regs) struct device *dev = NULL; /* ops is a ptr list for several fs_ops */ const struct fs_ops **ops = (const struct fs_ops **)regs->eax.l; - + /* Initialize malloc() */ mem_init(); - + /* Default name for the root directory */ fs.cwd_name[0] = '/'; |