LZO
LZO is a compression library offering fast compression and very fast decompression.
Website: https://www.oberhumer.com/opensource/lzo/
Platforms supported: Windows (32-bit and 64-bit), Linux, FreeBSD, Haiku
Headers to include: lzo/lzo.bi
Header version: 2.09
Haiku R1 beta 6 amd64: `examples/manual/libraries/lzo.bas` compiled and ran
with FreeBASIC 1.20.4-3 against HaikuPorts LZO 2.10; its compression and safe
decompression round trip matched the original bytes.
The example uses the upstream LZO1X worst-case compression capacity input + input \ 16 + 64 + 3, allocates the exact expected decoded capacity, and calls lzo1x_decompress_safe. It validates the decoded length and every input byte, including the terminator, before displaying the text. The source, output and compression workspace use separate ownership paths.
Windows qualification uses the installed LZO 2.10 SDK on both architectures and compares the integer, alignment and workspace declarations with its native C headers. The input is a fixed demonstration string; this example does not define a file format for storing compressed data.
Website: https://www.oberhumer.com/opensource/lzo/
Platforms supported: Windows (32-bit and 64-bit), Linux, FreeBSD, Haiku
Headers to include: lzo/lzo.bi
Header version: 2.09
Haiku R1 beta 6 amd64: `examples/manual/libraries/lzo.bas` compiled and ran
with FreeBASIC 1.20.4-3 against HaikuPorts LZO 2.10; its compression and safe
decompression round trip matched the original bytes.
The example uses the upstream LZO1X worst-case compression capacity input + input \ 16 + 64 + 3, allocates the exact expected decoded capacity, and calls lzo1x_decompress_safe. It validates the decoded length and every input byte, including the terminator, before displaying the text. The source, output and compression workspace use separate ownership paths.
Windows qualification uses the installed LZO 2.10 SDK on both architectures and compares the integer, alignment and workspace declarations with its native C headers. The input is a fixed demonstration string; this example does not define a file format for storing compressed data.
Example
'' examples/manual/libraries/lzo.bas
''
'' Example extracted from the FreeBASIC Manual
'' from topic 'LZO'
''
'' See Also: https://www.freebasic.net/wiki/wikka.php?wakka=ExtLibLzo
'' --------
'' Purpose: Demonstrate a checked in-memory LZO round trip.
'' Responsibilities: Bound output buffers, validate decoded bytes, and release owned memory.
'' This file contains no file I/O or external compressed input.
'' Ownership:
'' The example owns the compressed and decompressed buffers after allocation.
'' The compression workspace is released after compression, and every failure
'' path clears the pointers it has released before ending the program.
#include "lzo/lzo1x.bi"
#include Once "crt/string.bi"
Dim inbuf As ZString Ptr = @"string to compress (or not, since it's so short)"
Dim inlen As lzo_uint = Len(*inbuf) + 1
'' The LZO simple.c example reserves this worst-case LZO1X output size.
Dim complen As lzo_uint = inlen + inlen \ 16 + 64 + 3
Dim compbuf As ZString Ptr
Dim decomplen As lzo_uint = inlen
Dim decompbuf As ZString Ptr
Dim workmem As Any Ptr
Print "initializing LZO: ";
If lzo_init() = 0 Then
Print "ok"
Else
Print "failed!"
End 1
End If
compbuf = Allocate(complen)
If compbuf = 0 Then
Print "unable to allocate compression buffer"
End 1
End If
decompbuf = Allocate(decomplen)
If decompbuf = 0 Then
Deallocate(compbuf)
compbuf = 0
Print "unable to allocate decompression buffer"
End 1
End If
Print "compressing '" & *inbuf & "': ";
workmem = Allocate(LZO1X_1_15_MEM_COMPRESS)
If workmem = 0 Then
Deallocate(compbuf)
compbuf = 0
Deallocate(decompbuf)
decompbuf = 0
Print "unable to allocate compression workspace"
End 1
End If
If lzo1x_1_15_compress(inbuf, inlen, compbuf, @complen, workmem) = 0 Then
Print "ok (" & inlen & " bytes in, " & complen & " bytes compressed)"
Else
Deallocate(workmem)
workmem = 0
Deallocate(compbuf)
compbuf = 0
Deallocate(decompbuf)
decompbuf = 0
Print "failed!"
End 1
End If
Deallocate(workmem)
workmem = 0
Print "decompressing: ";
Dim result As Long = lzo1x_decompress_safe(compbuf, complen, decompbuf, @decomplen, NULL)
'' Validate all bytes, including the terminator, before displaying a ZSTRING.
If result = 0 AndAlso decomplen = inlen AndAlso memcmp(inbuf, decompbuf, inlen) = 0 Then
Print "ok: '" & *decompbuf & "' (" & complen & " bytes compressed, " & decomplen & " bytes decompressed)"
Else
Deallocate(compbuf)
compbuf = 0
Deallocate(decompbuf)
decompbuf = 0
Print "failed!"
End 1
End If
Deallocate(compbuf)
compbuf = 0
Deallocate(decompbuf)
decompbuf = 0
'' end of lzo.bas
''
'' Example extracted from the FreeBASIC Manual
'' from topic 'LZO'
''
'' See Also: https://www.freebasic.net/wiki/wikka.php?wakka=ExtLibLzo
'' --------
'' Purpose: Demonstrate a checked in-memory LZO round trip.
'' Responsibilities: Bound output buffers, validate decoded bytes, and release owned memory.
'' This file contains no file I/O or external compressed input.
'' Ownership:
'' The example owns the compressed and decompressed buffers after allocation.
'' The compression workspace is released after compression, and every failure
'' path clears the pointers it has released before ending the program.
#include "lzo/lzo1x.bi"
#include Once "crt/string.bi"
Dim inbuf As ZString Ptr = @"string to compress (or not, since it's so short)"
Dim inlen As lzo_uint = Len(*inbuf) + 1
'' The LZO simple.c example reserves this worst-case LZO1X output size.
Dim complen As lzo_uint = inlen + inlen \ 16 + 64 + 3
Dim compbuf As ZString Ptr
Dim decomplen As lzo_uint = inlen
Dim decompbuf As ZString Ptr
Dim workmem As Any Ptr
Print "initializing LZO: ";
If lzo_init() = 0 Then
Print "ok"
Else
Print "failed!"
End 1
End If
compbuf = Allocate(complen)
If compbuf = 0 Then
Print "unable to allocate compression buffer"
End 1
End If
decompbuf = Allocate(decomplen)
If decompbuf = 0 Then
Deallocate(compbuf)
compbuf = 0
Print "unable to allocate decompression buffer"
End 1
End If
Print "compressing '" & *inbuf & "': ";
workmem = Allocate(LZO1X_1_15_MEM_COMPRESS)
If workmem = 0 Then
Deallocate(compbuf)
compbuf = 0
Deallocate(decompbuf)
decompbuf = 0
Print "unable to allocate compression workspace"
End 1
End If
If lzo1x_1_15_compress(inbuf, inlen, compbuf, @complen, workmem) = 0 Then
Print "ok (" & inlen & " bytes in, " & complen & " bytes compressed)"
Else
Deallocate(workmem)
workmem = 0
Deallocate(compbuf)
compbuf = 0
Deallocate(decompbuf)
decompbuf = 0
Print "failed!"
End 1
End If
Deallocate(workmem)
workmem = 0
Print "decompressing: ";
Dim result As Long = lzo1x_decompress_safe(compbuf, complen, decompbuf, @decomplen, NULL)
'' Validate all bytes, including the terminator, before displaying a ZSTRING.
If result = 0 AndAlso decomplen = inlen AndAlso memcmp(inbuf, decompbuf, inlen) = 0 Then
Print "ok: '" & *decompbuf & "' (" & complen & " bytes compressed, " & decomplen & " bytes decompressed)"
Else
Deallocate(compbuf)
compbuf = 0
Deallocate(decompbuf)
decompbuf = 0
Print "failed!"
End 1
End If
Deallocate(compbuf)
compbuf = 0
Deallocate(decompbuf)
decompbuf = 0
'' end of lzo.bas