Added support for full seek operations

A rather involved upgrade for both files and directories, seek and
related functions are now completely supported:
- lfs_file_seek
- lfs_file_tell
- lfs_file_rewind
- lfs_file_size
- lfs_dir_seek
- lfs_dir_tell
- lfs_dir_rewind

This change also highlighted the concern that lfs_off_t is unsigned,
whereas off_t is traditionally signed. Unfortunately, lfs_off_t is
already used intensively through the codebase, so in focusing on
moving forward and avoiding getting bogged down by details, I'm going to
keep it as is and use the signed type lfs_soff_t where necessary.

1 files changed, 281 insertions, 0 deletions

diff --git a/tests/test_seek.sh b/tests/test_seek.sh
new file mode 100755
index 0000000..b385e8b
--- /dev/null
+++ b/tests/test_seek.sh
@@ -0,0 +1,281 @@
+#!/bin/bash
+set -eu
+
+SMALLSIZE=4
+MEDIUMSIZE=128
+LARGESIZE=132
+
+echo "=== Seek tests ==="
+rm -rf blocks
+tests/test.py << TEST
+    lfs_format(&lfs, &cfg) => 0;
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_mkdir(&lfs, "hello") => 0;
+    for (int i = 0; i < $LARGESIZE; i++) {
+        sprintf((char*)buffer, "hello/kitty%d", i);
+        lfs_file_open(&lfs, &file[0], (char*)buffer,
+                LFS_O_WRONLY | LFS_O_CREAT | LFS_O_APPEND) => 0;
+
+        size = strlen("kittycatcat");
+        memcpy(buffer, "kittycatcat", size);
+        for (int j = 0; j < $LARGESIZE; j++) {
+            lfs_file_write(&lfs, &file[0], buffer, size);
+        }
+
+        lfs_file_close(&lfs, &file[0]) => 0;
+    }
+    lfs_unmount(&lfs) => 0;
+TEST
+
+echo "--- Simple dir seek ---"
+tests/test.py << TEST
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_dir_open(&lfs, &dir[0], "hello") => 0;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, ".") => 0;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, "..") => 0;
+
+    lfs_soff_t pos;
+    int i;
+    for (i = 0; i < $SMALLSIZE; i++) {
+        sprintf((char*)buffer, "kitty%d", i);
+        lfs_dir_read(&lfs, &dir[0], &info) => 1;
+        strcmp(info.name, (char*)buffer) => 0;
+        pos = lfs_dir_tell(&lfs, &dir[0]);
+    }
+    pos >= 0 => 1;
+
+    lfs_dir_seek(&lfs, &dir[0], pos) => 0;
+    sprintf((char*)buffer, "kitty%d", i);
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, (char*)buffer) => 0;
+
+    lfs_dir_rewind(&lfs, &dir[0]) => 0;
+    sprintf((char*)buffer, "kitty%d", 0);
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, ".") => 0;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, "..") => 0;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, (char*)buffer) => 0;
+
+    lfs_dir_seek(&lfs, &dir[0], pos) => 0;
+    sprintf((char*)buffer, "kitty%d", i);
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, (char*)buffer) => 0;
+
+    lfs_dir_close(&lfs, &dir[0]) => 0;
+    lfs_unmount(&lfs) => 0;
+TEST
+
+echo "--- Large dir seek ---"
+tests/test.py << TEST
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_dir_open(&lfs, &dir[0], "hello") => 0;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, ".") => 0;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, "..") => 0;
+
+    lfs_soff_t pos;
+    int i;
+    for (i = 0; i < $MEDIUMSIZE; i++) {
+        sprintf((char*)buffer, "kitty%d", i);
+        lfs_dir_read(&lfs, &dir[0], &info) => 1;
+        strcmp(info.name, (char*)buffer) => 0;
+        pos = lfs_dir_tell(&lfs, &dir[0]);
+    }
+    pos >= 0 => 1;
+
+    lfs_dir_seek(&lfs, &dir[0], pos) => 0;
+    sprintf((char*)buffer, "kitty%d", i);
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, (char*)buffer) => 0;
+
+    lfs_dir_rewind(&lfs, &dir[0]) => 0;
+    sprintf((char*)buffer, "kitty%d", 0);
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, ".") => 0;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, "..") => 0;
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, (char*)buffer) => 0;
+
+    lfs_dir_seek(&lfs, &dir[0], pos) => 0;
+    sprintf((char*)buffer, "kitty%d", i);
+    lfs_dir_read(&lfs, &dir[0], &info) => 1;
+    strcmp(info.name, (char*)buffer) => 0;
+
+    lfs_dir_close(&lfs, &dir[0]) => 0;
+    lfs_unmount(&lfs) => 0;
+TEST
+
+echo "--- Simple file seek ---"
+tests/test.py << TEST
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_file_open(&lfs, &file[0], "hello/kitty42", LFS_O_RDONLY) => 0;
+
+    lfs_soff_t pos;
+    size = strlen("kittycatcat");
+    for (int i = 0; i < $SMALLSIZE; i++) {
+        lfs_file_read(&lfs, &file[0], buffer, size) => size;
+        memcmp(buffer, "kittycatcat", size) => 0;
+        pos = lfs_file_tell(&lfs, &file[0]);
+    }
+    pos >= 0 => 1;
+
+    lfs_file_seek(&lfs, &file[0], pos, LFS_SEEK_SET) => pos;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_file_rewind(&lfs, &file[0]) => 0;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_file_seek(&lfs, &file[0], pos, LFS_SEEK_SET) => size;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_file_seek(&lfs, &file[0], -size, LFS_SEEK_CUR) => pos+size;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_file_seek(&lfs, &file[0], -size, LFS_SEEK_END) => pos+size;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_size_t size = lfs_file_size(&lfs, &file[0]);
+    lfs_file_seek(&lfs, &file[0], 0, LFS_SEEK_CUR) => size;
+
+    lfs_file_close(&lfs, &file[0]) => 0;
+    lfs_unmount(&lfs) => 0;
+TEST
+
+echo "--- Large file seek ---"
+tests/test.py << TEST
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_file_open(&lfs, &file[0], "hello/kitty42", LFS_O_RDONLY) => 0;
+
+    lfs_soff_t pos;
+    size = strlen("kittycatcat");
+    for (int i = 0; i < $MEDIUMSIZE; i++) {
+        lfs_file_read(&lfs, &file[0], buffer, size) => size;
+        memcmp(buffer, "kittycatcat", size) => 0;
+        pos = lfs_file_tell(&lfs, &file[0]);
+    }
+    pos >= 0 => 1;
+
+    lfs_file_seek(&lfs, &file[0], pos, LFS_SEEK_SET) => pos;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_file_rewind(&lfs, &file[0]) => 0;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_file_seek(&lfs, &file[0], pos, LFS_SEEK_SET) => size;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_file_seek(&lfs, &file[0], -size, LFS_SEEK_CUR) => pos+size;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_file_seek(&lfs, &file[0], -size, LFS_SEEK_END) => pos+size;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_size_t size = lfs_file_size(&lfs, &file[0]);
+    lfs_file_seek(&lfs, &file[0], 0, LFS_SEEK_CUR) => size;
+
+    lfs_file_close(&lfs, &file[0]) => 0;
+    lfs_unmount(&lfs) => 0;
+TEST
+
+echo "--- Simple file seek and write ---"
+tests/test.py << TEST
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_file_open(&lfs, &file[0], "hello/kitty42", LFS_O_RDWR) => 0;
+
+    lfs_soff_t pos;
+    size = strlen("kittycatcat");
+    for (int i = 0; i < $SMALLSIZE; i++) {
+        lfs_file_read(&lfs, &file[0], buffer, size) => size;
+        memcmp(buffer, "kittycatcat", size) => 0;
+        pos = lfs_file_tell(&lfs, &file[0]);
+    }
+    pos >= 0 => 1;
+
+    memcpy(buffer, "doggodogdog", size);
+    lfs_file_seek(&lfs, &file[0], pos, LFS_SEEK_SET) => pos;
+    lfs_file_write(&lfs, &file[0], buffer, size) => size;
+
+    lfs_file_seek(&lfs, &file[0], pos, LFS_SEEK_SET) => pos;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "doggodogdog", size) => 0;
+
+    lfs_file_rewind(&lfs, &file[0]) => 0;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_file_seek(&lfs, &file[0], pos, LFS_SEEK_SET) => size;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "doggodogdog", size) => 0;
+
+    lfs_file_seek(&lfs, &file[0], -size, LFS_SEEK_END) => pos+size;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_size_t size = lfs_file_size(&lfs, &file[0]);
+    lfs_file_seek(&lfs, &file[0], 0, LFS_SEEK_CUR) => size;
+
+    lfs_file_close(&lfs, &file[0]) => 0;
+    lfs_unmount(&lfs) => 0;
+TEST
+
+echo "--- Large file seek and write ---"
+tests/test.py << TEST
+    lfs_mount(&lfs, &cfg) => 0;
+    lfs_file_open(&lfs, &file[0], "hello/kitty42", LFS_O_RDWR) => 0;
+
+    lfs_soff_t pos;
+    size = strlen("kittycatcat");
+    for (int i = 0; i < $MEDIUMSIZE; i++) {
+        lfs_file_read(&lfs, &file[0], buffer, size) => size;
+        if (i != $SMALLSIZE) {
+            memcmp(buffer, "kittycatcat", size) => 0;
+        }
+        pos = lfs_file_tell(&lfs, &file[0]);
+    }
+    pos >= 0 => 1;
+
+    memcpy(buffer, "doggodogdog", size);
+    lfs_file_seek(&lfs, &file[0], pos, LFS_SEEK_SET) => pos;
+    lfs_file_write(&lfs, &file[0], buffer, size) => size;
+
+    lfs_file_seek(&lfs, &file[0], pos, LFS_SEEK_SET) => pos;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "doggodogdog", size) => 0;
+
+    lfs_file_rewind(&lfs, &file[0]) => 0;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_file_seek(&lfs, &file[0], pos, LFS_SEEK_SET) => size;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "doggodogdog", size) => 0;
+
+    lfs_file_seek(&lfs, &file[0], -size, LFS_SEEK_END) => pos+size;
+    lfs_file_read(&lfs, &file[0], buffer, size) => size;
+    memcmp(buffer, "kittycatcat", size) => 0;
+
+    lfs_size_t size = lfs_file_size(&lfs, &file[0]);
+    lfs_file_seek(&lfs, &file[0], 0, LFS_SEEK_CUR) => size;
+
+    lfs_file_close(&lfs, &file[0]) => 0;
+    lfs_unmount(&lfs) => 0;
+TEST
+
+echo "--- Results ---"
+tests/stats.py