switch to blake2

[zpackage] / lib / uncompress.c

diff --git a/lib/uncompress.c b/lib/uncompress.c
index 9fddaf24cafac58a0aa97aa84faf15146e87efdb..b8e0b674fc089512875b08e1b028fd00d12baced 100644 (file)
--- a/lib/uncompress.c
+++ b/lib/uncompress.c
@@ -4,16 +4,122 @@
 #include <fcntl.h>
 #include <unistd.h>
 #include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <assert.h>
 
 #include <sys/mman.h>
 
-#include "sha256.h"
-
 #include "lzma.h"
 
-void uncompresslzma(void *buf, size_t bufsize, FILE *out) {
+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;
+       ssize_t bytes = 0;
        
        uint8_t outbuf[BUFSIZ];
 
@@ -26,7 +132,7 @@ void uncompresslzma(void *buf, size_t bufsize, FILE *out) {
        if (ret != LZMA_OK) {
                fprintf(stderr, "%s", ret == LZMA_MEM_ERROR ? strerror(ENOMEM)
                                : "Internal error (bug)");
-               exit(EXIT_FAILURE);
+               return -1;
        }
 
        strm->avail_in = bufsize;
@@ -43,15 +149,27 @@ void uncompresslzma(void *buf, size_t bufsize, FILE *out) {
                // 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) {
-                       const size_t write_size = BUFSIZ - strm->avail_out;
-
-                       if (fwrite(outbuf, 1, write_size, out) != write_size) {
-                               // Wouldn't be a surprise if writing to stderr
-                               // would fail too but at least try to show an
-                               // error message.
-                               fprintf(stderr, "Cannot write to output file stream: "
-                                               "%s", strerror(errno));
-                               exit(EXIT_FAILURE);
+                       size_t avail = BUFSIZ - strm->avail_out;
+                       ssize_t written = 0;
+                       uint8_t *start;
+
+                       start = outbuf;
+
+                       while (avail > 0) {
+                               written = write(out, 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.
+                                        */
+                                       fprintf(stderr, "Cannot write to output"
+                                                       " file stream: %s",
+                                                       strerror(errno));
+                                       return -1;
+                               }
+                               avail -= written;
+                               start += written;
+                               bytes += written;
                        }
 
                        strm->next_out = outbuf;
@@ -64,9 +182,11 @@ void uncompresslzma(void *buf, size_t bufsize, FILE *out) {
                                // that there's no trailing garbage.
                                assert(strm->avail_in == 0);
                                //assert(action == LZMA_FINISH);
-                               return;
+                               lzma_end(strm);
+                               return bytes;
                        }
 
+                       lzma_end(strm);
                        const char *msg;
                        switch (ret) {
                                case LZMA_MEM_ERROR:
@@ -95,8 +215,8 @@ void uncompresslzma(void *buf, size_t bufsize, FILE *out) {
                                        break;
                        }
 
-                       fprintf(stderr, "xz: %s\n", msg);
-                       exit(EXIT_FAILURE);
+                       fprintf(stderr, "zpmuncompress: %s\n", msg);
+                       return -1;
                }
        }
 }