Jonathan and I just put together Plausible Database, a small Objective-C SQLite library for our iPhone development. The API is intended to allow support for additional databases, but SQLite is clearly the primary target on the phone.
The 1.0 "preview release", including doxygen-generated API documentation, is available via Google Code (BSD license). The code has 100% unit test coverage, and should work for both Mac OS X and NDA-covered SDKs of an indeterminate nature. It's a relatively small bit of code, but we'd appreciate any feedback on the API or implementation -- including your thoughts on supporting future database back-ends, such as PostgreSQL. The API was inspired by public domain SQLite code (FMDB) from Gus Mueller of Flying Meat.
We have used the library to implement a small transactional schema migration library for our applications -- SQLite has a super handy per-database "user_version" which can be used for this.
Here are some usage examples:
/* Create and open an in-memory database */
PLSqliteDatabase *db = [[PLSqliteDatabase alloc] initWithPath: @":memory:"];
if (![db open])
NSLog(@"Could not open database");
/* Create a table and add some data */
if (![db executeUpdate: @"CREATE TABLE example (id INTEGER)"])
NSLog(@"Table creation failed");
if (![db executeUpdate: @"INSERT INTO example (id) VALUES (?)", [NSNumber numberWithInteger: 42]])
NSLog(@"Data insert failed");
/* Execute a query */ NSObject22:14 Tue, 23 Oct 2007 PDT -0700*results = [db executeQuery: @"SELECT id FROM example WHERE id = ?", [NSNumber numberWithInteger: 42]]; while ([results next]) { NSLog(@"Value of column id is %d", [results intForColumn: @"id"]); } /* Failure to close the result set will not leak memory, but may * retain database resources until the instance is deallocated. */ [results close];
NOTE: This post has been archived for historical purposes. The toolchain has advanced considerably, and Apple is planning to release their own SDK. I plan to hold out on further development, toolchain or otherwise, until it's released.
Please see iPhone Toolchain Project for up-to-date instructions.
To facilitate my own iPhone development, I've committed three new ports for the iphone-binutils project to MacPorts. Once installed, you're ready to compile Hello, World. Prior to installation, you'll need to acquire a copy of the iPhone root disk image ("Heavenly") and install its contents in /opt/local/arm-apple-darwin/heavenly. The image is required to provide the necessary libraries for linking cross-compiled iPhone binaries, and can't be re-distributed.
To start, download and decompress iPhone1,1_1.0_1A543a_Restore.ipsw:
user@host> curl -O http://appldnld.apple.com.edgesuite.net/content.info.apple.com/iPhone/061-3538.20070629.B7vXa/iPhone1,1_1.0_1A543a_Restore.ipsw user@host> unzip iPhone1,1_1.0_1A543a_Restore.ipsw \*.dmg
This will extract two disk images: "694-5259-38.dmg" and "694-5262-39.dmg". The encrypted "694-5262-39.dmg" disk image contains the iPhone root. The decryption key for this image is stored in plain text within the "asr" binary on the corresponding "694-5259-38.dmg". To retrieve the key, run the following:
user@host> strings 694-5259-38.dmg| grep "^[0-9a-fA-F]*$" | awk '{ if (length($1) == 72) print; }'
This should output a 72 character hex string, which you'll use as the decryption key.
In order to perform the decryption, you'll need modified 'vfdecrypt' -- a command utility for decrypting Mac OS X disk images. The source is available here. To compile, simply type "make" in the vfdecrypt-iphone directory. The provided version of vfdecrypt was slightly modified to support direct input of the private AES and SHA1 HMAC keys -- these are normally wrapped with a user-supplied passphrase (via 3DES-EDE), which is not available. vfdecrypt was written by Ralf-Philipp Weinmann, Jacob Appelbaum, and Christian Fromme.
Once you've build vfdecrypt, use it to decrypt the disk image:
user@host> ~/vfdecrypt-iphone/vfdecrypt -i 694-5262-39.dmg -k <hex key> -o heavenly.dmg
Now, mount the disk image and copy the contents to /opt/local/arm-apple-darwin/heavenly:
user@host> open heavenly.dmg user@host> sudo mkdir -p /opt/local/arm-apple-darwin/heavenly user@host> (cd /Volumes/Heavenly1A543a.UserBundle && tar cf - .) | (cd /opt/local/arm-apple-darwin/heavenly && sudo tar xvf -)
To install the toolchain:
sudo port install arm-apple-darwin-runtime
You should now be able to compile standard Unix software:
CC=arm-apple-darwin-cc CPP=llvm-cpp ./configure --host=arm-apple-darwin
For more information on compiling your first GUI application, check out the UIKit Hello World