void do_symlink(const u8 * base, u32 offset, u32 size, const char *path, const char *name, int mode) {
// Allocate the uncompressed string
u8 link_contents[size + 1];
// do uncompression
uncompress_data(base, base + offset, size, link_contents);
link_contents[size] = 0;
printsize(size, compressed_size(base, base + offset, size));
printf("%s -> %s", name, link_contents);
// Check if we are actually unpacking
if (path[0] == '-') {
return;
}
// Make local copy
if (symlink((const char *)link_contents, path) == -1) {
perror(path);
exit(1);
}
}
bool compressed_output_stream::flush() {
VAST_ENTER();
if (valid_bytes_ == 0)
VAST_RETURN(true);
void* dst_data;
size_t dst_size;
if (!sink_.raw(&dst_data, &dst_size))
VAST_RETURN(false);
auto compressed_bound = compressed_size(valid_bytes_);
compressed_.resize(compressed_bound);
size_t n;
if (4 + compressed_bound > dst_size) {
// Block may be too large for the output stream buffer. Thus we need to
// compress it first into a temporary buffer and then write it out in raw
// form.
n = compress(compressed_.data(), compressed_.size());
VAST_ASSERT(n > 0);
VAST_ASSERT(n <= std::numeric_limits<uint32_t>::max());
VAST_ASSERT(n <= compressed_bound);
total_bytes_ += sink_.write<uint32_t>(&n);
total_bytes_ += sink_.write_raw(compressed_.data(), n);
} else {
// We have enough space to directly write the full block into the
// underlying output buffer, no need to use the scratch space.
n = compress(4 + reinterpret_cast<uint8_t*>(dst_data), compressed_.size());
VAST_ASSERT(n > 0);
VAST_ASSERT(n <= std::numeric_limits<uint32_t>::max());
VAST_ASSERT(n <= compressed_bound);
auto four = sink_.write<uint32_t>(&n);
if (four != sizeof(uint32_t))
VAST_RETURN(false);
total_bytes_ += four + n;
sink_.skip(n);
}
valid_bytes_ = 0;
VAST_RETURN(true);
}
void do_file(const u8* base, u32 offset, u32 size,
const char* path, const char* name, int mode)
{
int fd;
u8* file_data;
const u8* srcdata;
// Allow for uncompressed XIP executable
if (mode & S_ISVTX) {
// It seems that the offset may not necessarily be page
// aligned. This is silly because mkcramfs wastes
// the alignment space, whereas it might be used if it wasn't
// bogusly in our file extent.
//
// blksize must be a power of 2 for the following to work, but it seems
// quite likely.
srcdata=(const u8*)(((u32)(base+offset)+blksize-1) & ~(blksize-1));
printsize(size, srcdata+size-(base+offset));
printf("%s", name);
} else {
printsize(size, compressed_size(base, base+offset, size) );
printf("%s", name);
}
// Check if we are actually unpacking
if (path[0]=='-') {
return;
}
// Make local copy
fd=open(path, O_CREAT|O_TRUNC|O_RDWR, mode);
if (fd == -1) {
perror("create");
return;
};
if (ftruncate(fd, size) == -1) {
perror("ftruncate");
close(fd);
return;
}
file_data = mmap(0, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
if (file_data == MAP_FAILED) {
perror("mmap");
close(fd);
return;
}
// Allow for uncompressed XIP executable
if (mode & S_ISVTX) {
memcpy(file_data, srcdata, size);
} else {
if(uncompress_data(base, base+offset, size, file_data) == -1)
{
printf("failed to decompress data\n");
}
}
munmap(file_data, size);
close(fd);
}
