add wrapper function around libarchive to c++ errors

This commit is contained in:
Yorick 2019-12-07 23:10:27 +07:00
parent 232b390766
commit f54c168031
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GPG key ID: A36E70F9DC014A15

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@ -18,6 +18,14 @@ std::shared_ptr<struct archive> archive_read_ptr() {
archive_read_free(p);
});
}
static void ac(std::shared_ptr<struct archive> a, int r, const char* str = "archive is corrupt (%s)") {
if (r == ARCHIVE_EOF) {
throw EndOfFile("tar ended");
}
if (r != ARCHIVE_OK) {
throw Error(str, archive_error_string(a.get()));
}
}
void archive_read_open_source(std::shared_ptr<struct archive> a, Source& s, unsigned int bufsize = 1024) {
std::shared_ptr<unsigned char> buffer((unsigned char*)malloc(bufsize), [](auto p) { free(p); });
typedef struct {
@ -26,7 +34,7 @@ void archive_read_open_source(std::shared_ptr<struct archive> a, Source& s, unsi
unsigned int bs;
} St;
St* state = new St({buffer, s, bufsize});
if (archive_read_open(a.get(), state,
ac(a, archive_read_open(a.get(), state,
NULL /* open */,
([] (struct archive*, void* sptr, const void** buf) -> long int {
St& s = *(static_cast<St*>(sptr));
@ -40,9 +48,7 @@ void archive_read_open_source(std::shared_ptr<struct archive> a, Source& s, unsi
}), [] (struct archive*, void* sptr) {
delete static_cast<St*>(sptr);
return ARCHIVE_OK;
})) {
throw Error("archive is corrupt (%s)", archive_error_string(a.get()));
}
}));
}
std::shared_ptr<struct archive> archive_write_ptr() {
return std::shared_ptr<struct archive>(archive_write_disk_new(),
@ -53,28 +59,27 @@ std::shared_ptr<struct archive> archive_write_ptr() {
}
static void copy_data(std::shared_ptr<struct archive> ar, std::shared_ptr<struct archive> aw)
{
int r;
const void *buff;
size_t size;
la_int64_t offset;
for (;;) {
r = archive_read_data_block(ar.get(), &buff, &size, &offset);
if (r == ARCHIVE_EOF) return;
if (r != ARCHIVE_OK) {
throw Error("archive is corrupt (%s)", archive_error_string(ar.get()));
}
r = archive_write_data_block(aw.get(), buff, size, offset);
if (r != ARCHIVE_OK) {
throw Error("could not write archive output (%s)", archive_error_string(aw.get()));
try {
ac(ar, archive_read_data_block(ar.get(), &buff, &size, &offset));
} catch (EndOfFile &) {
return;
}
ac(aw, archive_write_data_block(aw.get(), buff, size, offset), "could not write archive output (%s)");
}
}
static void extract_archive(std::shared_ptr<struct archive> a, const Path & destDir) {
char * cwd = getcwd(0, 0);
if (!cwd) throw SysError("getting current directory");
Finally freeCwd([&]() { chdir(cwd); free(cwd); });
Finally backCwd([&]() {
int r = chdir(cwd);
free(cwd);
if (r != 0) throw SysError("resetting directory after archive extraction");
});
int r = chdir(destDir.c_str());
if (r != 0) throw SysError("setting directory to tar output path");
struct archive_entry *entry;
@ -90,16 +95,12 @@ static void extract_archive(std::shared_ptr<struct archive> a, const Path & dest
if (r == ARCHIVE_WARN) {
std::cerr << "warning: " << archive_error_string(a.get());
} else if (r < ARCHIVE_WARN) {
throw Error("archive is corrupt (%s)", archive_error_string(a.get()));
}
r = archive_write_header(ext.get(), entry);
if (r != ARCHIVE_OK) {
throw Error("could not write archive output (%s)", archive_error_string(ext.get()));
ac(a, r);
}
ac(ext, archive_write_header(ext.get(), entry), "could not write archive output (%s)");
copy_data(a, ext);
archive_write_finish_entry(ext.get());
}
//if (r != 0) throw SysError("resetting directory after archive extraction");
}
void unpackTarfile(Source & source, const Path & destDir)
{
@ -115,10 +116,7 @@ void unpackTarfile(const Path & tarFile, const Path & destDir)
auto a = archive_read_ptr();
archive_read_support_filter_all(a.get());
archive_read_support_format_all(a.get());
int r = archive_read_open_filename(a.get(), tarFile.c_str(), 16384);
if (r != ARCHIVE_OK) {
throw Error("archive is corrupt (%s)", archive_error_string(a.get()));
}
ac(a, archive_read_open_filename(a.get(), tarFile.c_str(), 16384));
createDirs(destDir);
extract_archive(a, destDir);
}