Add IsoFileSource implementation for local filesystem.

Makefile.am

@@ -14,6 +14,7 @@ src_libisofs_la_SOURCES = \
 	src/node.c \
 	src/image.h \
 	src/fsource.h \
+	src/fsource.c \
 	src/fs_local.c \
 	src/stream.h 
 libinclude_HEADERS = \

TODO

@@ -8,6 +8,7 @@ TODO
 #00001 (tree.h) -> consider adding new timestamps to IsoTreeNode
 #00002 (tree.h) -> handle deletion of each kind of node 
 #00003 make error.h header public
+#00004 (fsource-h) -> Add a get_mime_type() function.
 
 FIXME
 =====

src/error.h

@@ -14,8 +14,23 @@
  */
 
 #define ISO_SUCCESS				1
-#define ISO_NULL_POINTER		-1
+#define ISO_ERROR				-1
+#define ISO_NULL_POINTER		-2
+#define ISO_OUT_OF_MEM			-3
+#define ISO_MEM_ERROR			-4
+#define ISO_INTERRUPTED			-5
+#define ISO_WRONG_ARG_VALUE		-6
 
+#define ISO_FILE_ERROR					-100
+#define ISO_FILE_ALREADY_OPENNED		-101
+#define ISO_FILE_ACCESS_DENIED			-102
+#define ISO_FILE_BAD_PATH				-103
+#define ISO_FILE_DOESNT_EXIST			-104
+#define ISO_FILE_NOT_OPENNED			-105
+#define ISO_FILE_IS_DIR					-106
+#define ISO_FILE_READ_ERROR				-107
+#define ISO_FILE_IS_NOT_DIR				-108
+#define ISO_FILE_IS_NOT_SYMLINK			-109
 
 
 #endif /*LIBISO_ERROR_H_*/

src/fs_local.c

@@ -6,10 +6,354 @@
  * published by the Free Software Foundation. See COPYING file for details.
  */
 
- 
+
 /*
  * Filesystem/FileSource implementation to access the local filesystem.
  */
 
 #include "fsource.h"
+#include "error.h"
+
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <dirent.h>
+#include <unistd.h>
+#include <string.h>
+
+typedef struct
+{
+    /* IsoFilesystem *fs; It seems not needed */
+
+    char *path;
+    unsigned int openned:2; /* 0: not openned, 1: file, 2:dir */
+    union {
+        int fd;
+        DIR *dir;
+    } info;
+} _LocalFsFileSource;
+
+static
+const char* lfs_get_path(IsoFileSource *src)
+{
+    _LocalFsFileSource *data;
+    data = src->data;
+    return data->path;
+}
+
+static
+int lfs_lstat(IsoFileSource *src, struct stat *info)
+{
+    _LocalFsFileSource *data;
+
+    if (src == NULL || info == NULL) {
+        return ISO_NULL_POINTER;
+    }
+    data = src->data;
+
+    if (lstat(data->path, info) != 0) {
+        int err;
+
+        /* error, choose an appropriate return code */
+        switch(errno) {
+        case EACCES:
+            err = ISO_FILE_ACCESS_DENIED;
+            break;
+        case ENOTDIR:
+        case ENAMETOOLONG:
+        case ELOOP:
+            err = ISO_FILE_BAD_PATH;
+            break;
+        case ENOENT:
+            err = ISO_FILE_DOESNT_EXIST;
+            break;
+        case EFAULT:
+        case ENOMEM:
+            err = ISO_MEM_ERROR;
+            break;
+        default:
+            err = ISO_FILE_ERROR;
+            break;
+        }
+        return err;
+    }
+    return ISO_SUCCESS;
+}
+
+static
+int lfs_open(IsoFileSource *src)
+{
+    int err;
+    struct stat info;
+    _LocalFsFileSource *data;
+
+    if (src == NULL) {
+        return ISO_NULL_POINTER;
+    }
+
+    data = src->data;
+    if (data->openned) {
+        return ISO_FILE_ALREADY_OPENNED;
+    }
+
+    /* is a file or a dir ? */
+    err = lfs_lstat(src, &info);
+    if (err < 0) {
+        return err;
+    }
+
+    if (S_ISDIR(info.st_mode)) {
+        data->info.dir = opendir(data->path);
+        data->openned = data->info.dir ? 2 : 0;
+    } else {
+        data->info.fd = open(data->path, O_RDONLY);
+        data->openned = data->info.fd != -1 ? 1 : 0;
+    }
+
+    /*
+     * check for possible errors, note that many of possible ones are
+     * parsed in the lstat call above 
+     */
+    if (data->openned == 0) {
+        switch(errno) {
+        case EACCES:
+            err = ISO_FILE_ACCESS_DENIED;
+            break;
+        case EFAULT:
+        case ENOMEM:
+            err = ISO_MEM_ERROR;
+            break;
+        default:
+            err = ISO_FILE_ERROR;
+            break;
+        }
+        return err;
+    }
+
+    return ISO_SUCCESS;
+}
+
+static
+int lfs_close(IsoFileSource *src)
+{
+    _LocalFsFileSource *data;
+
+    if (src == NULL) {
+        return ISO_NULL_POINTER;
+    }
+
+    data = src->data;
+    switch(data->openned) {
+    case 1: /* not dir */
+        return close(data->info.fd) == 0 ? ISO_SUCCESS : ISO_FILE_ERROR;
+    case 2: /* directory */
+        return closedir(data->info.dir) == 0 ? ISO_SUCCESS : ISO_FILE_ERROR;
+    default:
+        return ISO_FILE_NOT_OPENNED;
+    }
+}
+
+static
+int lfs_read(IsoFileSource *src, void *buf, size_t count)
+{
+    _LocalFsFileSource *data;
+
+    if (src == NULL || buf == NULL) {
+        return ISO_NULL_POINTER;
+    }
+
+    data = src->data;
+    switch(data->openned) {
+    case 1: /* not dir */
+        {
+            int ret;
+            ret = read(data->info.fd, buf, count);
+            if (ret < 0) {
+                /* error on read */
+                switch(errno) {
+                case EINTR:
+                    ret = ISO_INTERRUPTED;
+                    break;
+                case EFAULT:
+                    ret = ISO_MEM_ERROR;
+                    break;
+                case EIO:
+                    ret = ISO_FILE_READ_ERROR;
+                    break;
+                default:
+                    ret = ISO_FILE_ERROR;
+                    break;
+                }
+            }
+            return ret;
+        }
+    case 2: /* directory */
+        return ISO_FILE_IS_DIR;
+    default:
+        return ISO_FILE_NOT_OPENNED;
+    }
+}
+
+static
+int lfs_readdir(IsoFileSource *src, IsoFileSource **child)
+{
+    _LocalFsFileSource *data;
+
+    if (src == NULL || child == NULL) {
+        return ISO_NULL_POINTER;
+    }
+
+    data = src->data;
+    switch(data->openned) {
+    case 1: /* not dir */
+        return ISO_FILE_IS_NOT_DIR;
+    case 2: /* directory */
+        {
+            char *path;
+            struct dirent *entry;
+            size_t a, b;
+            int ret;
+
+            entry = readdir(data->info.dir);
+            if (entry == NULL) {
+                if (errno == EBADF)
+                    return ISO_FILE_ERROR;
+                else
+                    return 0; /* EOF */
+            }
+
+            /* constructs the new path */
+            a = strlen(data->path);
+            b = strlen(entry->d_name);
+            path = malloc(a + b + 2);
+            if (path == NULL) {
+                return ISO_MEM_ERROR;
+            }
+            strncpy(path, data->path, a);
+            path[a] = '/';
+            path[a + 1] = '\0';
+            strncat(path, entry->d_name, b);
+
+            /* create the new FileSrc */
+            ret = iso_file_source_new_lfs(path, child);
+            if (ret < 0) {
+                free(path);
+            }
+            return ret;
+        }
+    default:
+        return ISO_FILE_NOT_OPENNED;
+    }
+}
+
+static
+int lfs_readlink(IsoFileSource *src, char *buf, size_t bufsiz)
+{
+    int size;
+    _LocalFsFileSource *data;
+
+    if (src == NULL || buf == NULL) {
+        return ISO_NULL_POINTER;
+    }
+
+    if (bufsiz <= 0) {
+        return ISO_WRONG_ARG_VALUE;
+    }
+
+    data = src->data;
+
+    /*
+     * invoke readlink, with bufsiz -1 to reserve an space for
+     * the NULL character
+     */
+    size = readlink(data->path, buf, bufsiz - 1);
+    if (size < 0) {
+        /* error */
+        switch(errno) {
+        case EACCES:
+            return ISO_FILE_ACCESS_DENIED;
+        case ENOTDIR:
+        case ENAMETOOLONG:
+        case ELOOP:
+            return ISO_FILE_BAD_PATH;
+        case ENOENT:
+            return ISO_FILE_DOESNT_EXIST;
+        case EINVAL:
+            return ISO_FILE_IS_NOT_SYMLINK;
+        case EFAULT:
+        case ENOMEM:
+            return ISO_MEM_ERROR;
+        default:
+            return ISO_FILE_ERROR;
+        }
+    }
+
+    /* NULL-terminate the buf */
+    buf[size] = '\0';
+    return ISO_SUCCESS;
+}
+
+static
+void lfs_free(IsoFileSource *src)
+{
+    _LocalFsFileSource *data;
+
+    data = src->data;
+
+    /* close the file if it is already openned */
+    if (data->openned) {
+        src->close(src);
+    }
+
+    free(data->path);
+    free(data);
+}
+
+/**
+ * 
+ * @return
+ *     1 success, < 0 error
+ */
+int iso_file_source_new_lfs(char *path, IsoFileSource **src)
+{
+    IsoFileSource *lfs_src;
+    _LocalFsFileSource *data;
+
+    if (src == NULL) {
+        return ISO_NULL_POINTER;
+    }
+
+    /* allocate memory */
+    data = malloc(sizeof(_LocalFsFileSource));
+    if (data == NULL) {
+        return ISO_OUT_OF_MEM;
+    }
+    lfs_src = malloc(sizeof(IsoFileSource));
+    if (lfs_src == NULL) {
+        free(data);
+        return ISO_OUT_OF_MEM;
+    }
+
+    /* fill struct */
+    data->path = path;
+    data->openned = 0;
+
+    lfs_src->refcount = 1;
+    lfs_src->data = data;
+    lfs_src->get_path = lfs_get_path;
+    lfs_src->lstat = lfs_lstat;
+    lfs_src->open = lfs_open;
+    lfs_src->close = lfs_close;
+    lfs_src->read = lfs_read;
+    lfs_src->readdir = lfs_readdir;
+    lfs_src->readlink = lfs_readlink;
+    lfs_src->free = lfs_free;
+
+    /* return */
+    *src = lfs_src;
+    return ISO_SUCCESS;
+}
+
 

src/fsource.c

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2007 Vreixo Formoso
+ * 
+ * This file is part of the libisofs project; you can redistribute it and/or 
+ * modify it under the terms of the GNU General Public License version 2 as 
+ * published by the Free Software Foundation. See COPYING file for details.
+ */
+
+#include "fsource.h"
+#include <stdlib.h>
+
+void iso_file_source_ref(IsoFileSource *src)
+{
+	++src->refcount;
+}
+
+void iso_file_source_unref(IsoFileSource *src)
+{
+	if (--src->refcount == 0) {
+		src->free(src);
+		free(src);
+	}
+}

src/fsource.h

@@ -40,22 +40,52 @@ struct Iso_File_Source
 {
 
     /**
+     * Get the path, relative to the filesystem this file source
+     * belongs to.
      * 
      * @return
-     * 		1 success, < 0 error
+     *     the path, that belong to the IsoFileSource and should not be
+     *     freed by the user.
+     */
+    const char* (*get_path)(IsoFileSource *src);
+
+    /**
+     * Get information about the file.
+     * @return
+     *    1 success, < 0 error
+     *      Error codes:
+     *         ISO_FILE_ACCESS_DENIED
+     *         ISO_FILE_BAD_PATH
+     *         ISO_FILE_DOESNT_EXIST
+     *         ISO_MEM_ERROR
+     *         ISO_FILE_ERROR
+     *         ISO_NULL_POINTER
      */
     int (*lstat)(IsoFileSource *src, struct stat *info);
 
-    //stat?
-
     /**
      * Opens the source.
      * @return 1 on success, < 0 on error
+     *      Error codes:
+     *         ISO_FILE_ALREADY_OPENNED
+     *         ISO_FILE_ACCESS_DENIED
+     *         ISO_FILE_BAD_PATH
+     *         ISO_FILE_DOESNT_EXIST
+     *         ISO_MEM_ERROR
+     *         ISO_FILE_ERROR
+     *         ISO_NULL_POINTER
      */
     int (*open)(IsoFileSource *src);
 
-
+    /**
-    void (*close)(IsoFileSource *src);
+     * Close a previuously openned file
+     * @return 1 on success, < 0 on error
+     *      Error codes:
+     *         ISO_FILE_ERROR
+     *         ISO_NULL_POINTER
+     *         ISO_FILE_NOT_OPENNED
+     */
+    int (*close)(IsoFileSource *src);
 
     /**
      * Attempts to read up to count bytes from the given source into
@@ -67,6 +97,13 @@ struct Iso_File_Source
      * 
      * @return 
      *     number of bytes read, 0 if EOF, < 0 on error
+     *      Error codes:
+     *         ISO_FILE_ERROR
+     *         ISO_NULL_POINTER
+     *         ISO_FILE_NOT_OPENNED
+     *         ISO_FILE_IS_DIR
+     *         ISO_MEM_ERROR
+     *         ISO_INTERRUPTED
      */
     int (*read)(IsoFileSource *src, void *buf, size_t count);
 
@@ -83,15 +120,63 @@ struct Iso_File_Source
      *     pointer to be filled with the given child. Undefined on error or OEF
      * @return 
      *     1 on success, 0 if EOF (no more children), < 0 on error
+     *      Error codes:
+     *         ISO_FILE_ERROR
+     *         ISO_NULL_POINTER
+     *         ISO_FILE_NOT_OPENNED
+     *         ISO_FILE_IS_NOT_DIR
+     *         ISO_MEM_ERROR
      */
     int (*readdir)(IsoFileSource *src, IsoFileSource **child);
 
     /**
+     * Read the destination of a symlink. You don't need to open the file
+     * to call this.
+     * 
+     * @param buf 
+     *     allocated buffer of at least bufsiz bytes. 
+     *     The dest. will be copied there, and it will be NULL-terminated
+     * @param bufsiz
+     *     characters to be copied. Destination link will be truncated if
+     *     it is larger than given size. This include the \0 character.
+     * @return 
+     *     1 on success, < 0 on error
+     *      Error codes:
+     *         ISO_FILE_ERROR
+     *         ISO_NULL_POINTER
+     *         ISO_WRONG_ARG_VALUE -> if bufsiz <= 0
+     *         ISO_FILE_IS_NOT_SYMLINK
+     *         ISO_MEM_ERROR
+     *         ISO_FILE_BAD_PATH
+     *         ISO_FILE_DOESNT_EXIST
      * 
      */
     int (*readlink)(IsoFileSource *src, char *buf, size_t bufsiz);
 
+    /**
+     * Free implementation specific data. Should never be called by user.
+     * Use iso_file_source_unref() instead.
+     */
+    void (*free)(IsoFileSource *src);
+
+    /*
+     * TODO #00004 Add a get_mime_type() function.
+     * This can be useful for GUI apps, to choose the icon of the file
+     */
+
+    //TODO define the refcount behavior for FileSources.
+    int refcount;
+    void *data;
 };
 
+void iso_file_source_ref(IsoFileSource *src);
+void iso_file_source_unref(IsoFileSource *src);
+
+/**
+ * Create a new IsoFileSource from a local filesystem path.
+ * While this is usually called by corresponding method in IsoFilesystem
+ * object, for local filesystem it is legal to call this directly.
+ */
+int iso_file_source_new_lfs(char *path, IsoFileSource **src);
 
 #endif /*LIBISO_FSOURCE_H_*/

src/image.h

@@ -11,6 +11,14 @@
 
 struct IsoImage {
 	
+	/*
+	 * Image is a context for image manipulation.
+	 * Global objects such as the message_queues must belogn to that
+	 * context. Thus we will have, for example, a msg queue per image,
+	 * so images are completelly independent and can be managed together.
+	 * (Usefull, for example, in Multiple-Document-Interface GUI apps.
+	 * [The stuff we have in init belongs really to image!]
+	 */
 	
 };