X-Git-Url: https://pd.if.org/git/?p=zpackage;a=blobdiff_plain;f=lib%2Funcompress.c;h=b8e0b674fc089512875b08e1b028fd00d12baced;hp=bbc1adbadfcfb3087fbbb67f0f608b8b7257dd61;hb=2ac486ab18adbbb84563eafc0d67fa8da6ca7822;hpb=4fb490d9107b747c86964d0d3925470b06d97c8c

diff --git a/lib/uncompress.c b/lib/uncompress.c
index bbc1adb..b8e0b67 100644
--- a/lib/uncompress.c
+++ b/lib/uncompress.c
@@ -12,6 +12,110 @@
 
 #include "lzma.h"
 
+ssize_t zpm_uncompress_cb(void *buf, size_t bufsize, void *cbdata,
+		int (*cb)(void *ud, void *buf, size_t bufsize)) {
+	lzma_stream s = LZMA_STREAM_INIT;
+	lzma_stream *strm;
+	ssize_t bytes = 0;
+	
+	uint8_t outbuf[BUFSIZ];
+
+	int ret;
+
+	strm = &s;
+
+	ret = lzma_stream_decoder(strm, UINT64_MAX, 0);
+	/* The only reasonable error here is LZMA_MEM_ERROR. */
+	if (ret != LZMA_OK) {
+		fprintf(stderr, "%s", ret == LZMA_MEM_ERROR ? strerror(ENOMEM)
+				: "Internal error (bug)");
+		return -1;
+	}
+
+	strm->avail_in = bufsize;
+	strm->next_in = buf;
+	strm->avail_out = BUFSIZ;
+	strm->next_out = outbuf;
+
+        lzma_action action = LZMA_RUN;
+
+	while (1) {
+		ret = lzma_code(strm, action);
+
+		// Write and check write error before checking decoder error.
+		// This way as much data as possible gets written to output
+		// even if decoder detected an error.
+		if (strm->avail_out == 0 || ret != LZMA_OK) {
+			size_t avail = BUFSIZ - strm->avail_out;
+			ssize_t written = 0;
+			uint8_t *start;
+
+			start = outbuf;
+
+			while (avail > 0) {
+				written = cb(cbdata, outbuf, avail);
+				if (written == -1) {
+					/* Wouldn't be a surprise if writing to
+					 * stderr would fail too but at least
+					 * try to show an error message.
+					 */
+					return -1;
+				}
+				avail -= written;
+				start += written;
+				bytes += written;
+			}
+
+			strm->next_out = outbuf;
+			strm->avail_out = BUFSIZ;
+		}
+
+		if (ret != LZMA_OK) {
+			if (ret == LZMA_STREAM_END) {
+				// lzma_stream_decoder() already guarantees
+				// that there's no trailing garbage.
+				assert(strm->avail_in == 0);
+				//assert(action == LZMA_FINISH);
+				lzma_end(strm);
+				return bytes;
+			}
+
+			lzma_end(strm);
+			const char *msg;
+			switch (ret) {
+				case LZMA_MEM_ERROR:
+					msg = strerror(ENOMEM);
+					break;
+
+				case LZMA_FORMAT_ERROR:
+					msg = "File format not recognized";
+					break;
+
+				case LZMA_OPTIONS_ERROR:
+					// FIXME: Better message?
+					msg = "Unsupported compression options";
+					break;
+
+				case LZMA_DATA_ERROR:
+					msg = "File is corrupt";
+					break;
+
+				case LZMA_BUF_ERROR:
+					msg = "Unexpected end of input";
+					break;
+
+				default:
+					msg = "Internal error (bug)";
+					break;
+			}
+
+			fprintf(stderr, "zpmuncompress: %s\n", msg);
+			return -1;
+		}
+	}
+
+}
+
 ssize_t uncompresslzma(void *buf, size_t bufsize, int out) {
 	lzma_stream s = LZMA_STREAM_INIT;
 	lzma_stream *strm;