Docs: Move xz_pipe_comp.c and xz_pipe_decomp.c to doc/examples_old.

It is good to keep these around to so that if someone has
copied the decompressor bug from xz_pipe_decomp.c he has
an example how to easily fix it.

1 files changed, 123 insertions, 0 deletions

diff --git a/doc/examples_old/xz_pipe_decomp.c b/doc/examples_old/xz_pipe_decomp.c
new file mode 100644
index 00000000..fb5ad895
--- /dev/null
+++ b/doc/examples_old/xz_pipe_decomp.c
@@ -0,0 +1,123 @@
+/*
+ * xz_pipe_decomp.c
+ * A simple example of pipe-only xz decompressor implementation.
+ * version: 2012-06-14 - by Daniel Mealha Cabrita
+ * Not copyrighted -- provided to the public domain.
+ *
+ * Compiling:
+ * Link with liblzma. GCC example:
+ * $ gcc -llzma xz_pipe_decomp.c -o xz_pipe_decomp
+ *
+ * Usage example:
+ * $ cat some_file.xz | ./xz_pipe_decomp > some_file
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <inttypes.h>
+#include <stdbool.h>
+#include <lzma.h>
+
+
+/* read/write buffer sizes */
+#define IN_BUF_MAX	4096
+#define OUT_BUF_MAX	4096
+
+/* error codes */
+#define RET_OK			0
+#define RET_ERROR_INIT		1
+#define RET_ERROR_INPUT		2
+#define RET_ERROR_OUTPUT	3
+#define RET_ERROR_DECOMPRESSION	4
+
+
+/* note: in_file and out_file must be open already */
+int xz_decompress (FILE *in_file, FILE *out_file)
+{
+	lzma_stream strm = LZMA_STREAM_INIT; /* alloc and init lzma_stream struct */
+	const uint32_t flags = LZMA_TELL_UNSUPPORTED_CHECK | LZMA_CONCATENATED;
+	const uint64_t memory_limit = UINT64_MAX; /* no memory limit */
+	uint8_t in_buf [IN_BUF_MAX];
+	uint8_t out_buf [OUT_BUF_MAX];
+	size_t in_len;	/* length of useful data in in_buf */
+	size_t out_len;	/* length of useful data in out_buf */
+	bool in_finished = false;
+	bool out_finished = false;
+	lzma_action action;
+	lzma_ret ret_xz;
+	int ret;
+
+	ret = RET_OK;
+
+	/* initialize xz decoder */
+	ret_xz = lzma_stream_decoder (&strm, memory_limit, flags);
+	if (ret_xz != LZMA_OK) {
+		fprintf (stderr, "lzma_stream_decoder error: %d\n", (int) ret_xz);
+		return RET_ERROR_INIT;
+	}
+
+	while ((! in_finished) && (! out_finished)) {
+		/* read incoming data */
+		in_len = fread (in_buf, 1, IN_BUF_MAX, in_file);
+
+		if (feof (in_file)) {
+			in_finished = true;
+		}
+		if (ferror (in_file)) {
+			in_finished = true;
+			ret = RET_ERROR_INPUT;
+		}
+
+		strm.next_in = in_buf;
+		strm.avail_in = in_len;
+
+		/* if no more data from in_buf, flushes the
+		   internal xz buffers and closes the decompressed data
+		   with LZMA_FINISH */
+		action = in_finished ? LZMA_FINISH : LZMA_RUN;
+
+		/* loop until there's no pending decompressed output */
+		do {
+			/* out_buf is clean at this point */
+			strm.next_out = out_buf;
+			strm.avail_out = OUT_BUF_MAX;
+
+			/* decompress data */
+			ret_xz = lzma_code (&strm, action);
+
+			if ((ret_xz != LZMA_OK) && (ret_xz != LZMA_STREAM_END)) {
+				fprintf (stderr, "lzma_code error: %d\n", (int) ret_xz);
+				out_finished = true;
+				ret = RET_ERROR_DECOMPRESSION;
+			} else {
+				/* write decompressed data */
+				out_len = OUT_BUF_MAX - strm.avail_out;
+				fwrite (out_buf, 1, out_len, out_file);
+				if (ferror (out_file)) {
+					out_finished = true;
+					ret = RET_ERROR_OUTPUT;
+				}
+			}
+		} while (strm.avail_out == 0);
+	}
+
+	/* Bug fix (2012-06-14): If no errors were detected, check
+	   that the last lzma_code() call returned LZMA_STREAM_END.
+	   If not, the file is probably truncated. */
+	if ((ret == RET_OK) && (ret_xz != LZMA_STREAM_END)) {
+		fprintf (stderr, "Input truncated or corrupt\n");
+		ret = RET_ERROR_DECOMPRESSION;
+	}
+
+	lzma_end (&strm);
+	return ret;
+}
+
+int main ()
+{
+	int ret;
+
+	ret = xz_decompress (stdin, stdout);
+	return ret;
+}
+