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// file : bpkg/host-os-release.cxx -*- C++ -*-
// license : MIT; see accompanying LICENSE file
#include <bpkg/host-os-release.hxx>
#include <libbutl/string-parser.hxx> // parse_quoted()
#include <bpkg/diagnostics.hxx>
using namespace butl;
namespace bpkg
{
// Note: not static for access from the unit test.
//
os_release
host_os_release_linux (path f = {})
{
os_release r;
// According to os-release(5), we should use /etc/os-release and fallback
// to /usr/lib/os-release if the former does not exist. It also lists the
// fallback values for individual variables, in case some are not present.
//
if (!f.empty ()
? exists (f)
: (exists (f = path ("/etc/os-release")) ||
exists (f = path ("/usr/lib/os-release"))))
{
try
{
ifdstream ifs (f, ifdstream::badbit);
string l;
for (uint64_t ln (1); !eof (getline (ifs, l)); ++ln)
{
trim (l);
// Skip blanks lines and comments.
//
if (l.empty () || l[0] == '#')
continue;
// The variable assignments are in the "shell style" and so can be
// quoted/escaped. For now we only handle quoting, which is what all
// the instances seen in the wild seems to use.
//
size_t p (l.find ('='));
if (p == string::npos)
continue;
string n (l, 0, p);
l.erase (0, p + 1);
using string_parser::parse_quoted;
using string_parser::invalid_string;
try
{
if (n == "ID_LIKE")
{
r.like_ids.clear ();
vector<string> vs (parse_quoted (l, true /* unquote */));
for (const string& v: vs)
{
for (size_t b (0), e (0); next_word (v, b, e); )
{
r.like_ids.push_back (string (v, b, e - b));
}
}
}
else if (string* p = (n == "ID" ? &r.name_id :
n == "VERSION_ID" ? &r.version_id :
n == "VARIANT_ID" ? &r.variant_id :
n == "NAME" ? &r.name :
n == "VERSION_CODENAME" ? &r.version_codename :
n == "VARIANT" ? &r.variant :
nullptr))
{
vector<string> vs (parse_quoted (l, true /* unquote */));
switch (vs.size ())
{
case 0: *p = ""; break;
case 1: *p = move (vs.front ()); break;
default: throw invalid_string (0, "multiple values");
}
}
}
catch (const invalid_string& e)
{
location loc (move (f).string (), ln);
fail (loc) << "invalid " << n << " value: " << e;
}
}
ifs.close ();
}
catch (const io_error& e)
{
fail << "unable to read from " << f << ": " << e;
}
}
// Assign fallback values.
//
if (r.name_id.empty ()) r.name_id = "linux";
if (r.name.empty ()) r.name = "Linux";
return r;
}
optional<os_release>
host_os_release (const target_triplet& host)
{
if (host.class_ == "linux")
return host_os_release_linux ();
else
return nullopt;
}
}
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