[libc-commits] [libc] [libc][NFC] Add FieldTokenizer and FlatFileDatabase (PR #214720)

[Alexey Samsonov via libc-commits]

================
@@ -13,196 +13,55 @@
 
 #include "src/pwd/pwd_utils.h"
 #include "hdr/errno_macros.h"
-#include "hdr/stdio_macros.h"
+#include "hdr/types/gid_t.h"
 #include "hdr/types/struct_passwd.h"
+#include "hdr/types/uid_t.h"
 #include "src/__support/CPP/span.h"
-#include "src/__support/File/file.h"
-#include "src/__support/ctype_utils.h"
-#include "src/__support/str_to_integer.h"
+#include "src/pwd/flat_file_db.h"
 #include "src/string/string_utils.h"
 
 #ifndef LIBC_COPT_PWD_FILE_PATH
 #define LIBC_COPT_PWD_FILE_PATH "/etc/passwd"
 #endif
 
 namespace LIBC_NAMESPACE_DECL {
-namespace internal {
+namespace pwd {
 
 ErrorOr<struct passwd> parse_passwd_line(char *line) {
   if (!line)
     return Error(EINVAL);
 
   struct passwd pwd;
-  char *context = line;
-
-  pwd.pw_name = string_token<false>(nullptr, ":", &context);
-  if (!pwd.pw_name)
-    return Error(EINVAL);
-
-  pwd.pw_passwd = string_token<false>(nullptr, ":", &context);
-  if (!pwd.pw_passwd)
-    return Error(EINVAL);
-
-  char *uid_str = string_token<false>(nullptr, ":", &context);
-  if (!uid_str || !isdigit(uid_str[0]))
-    return Error(EINVAL);
-  auto uid_res = strtointeger<uid_t>(uid_str, 10);
-  if (uid_res.has_error() || uid_res.parsed_len == 0 ||
-      uid_str[uid_res.parsed_len] != '\0')
-    return Error(EINVAL);
-  pwd.pw_uid = uid_res.value;
-
-  char *gid_str = string_token<false>(nullptr, ":", &context);
-  if (!gid_str || !isdigit(gid_str[0]))
-    return Error(EINVAL);
-  auto gid_res = strtointeger<gid_t>(gid_str, 10);
-  if (gid_res.has_error() || gid_res.parsed_len == 0 ||
-      gid_str[gid_res.parsed_len] != '\0')
-    return Error(EINVAL);
-  pwd.pw_gid = gid_res.value;
-
-  pwd.pw_gecos = string_token<false>(nullptr, ":", &context);
-  if (!pwd.pw_gecos)
-    return Error(EINVAL);
-
-  pwd.pw_dir = string_token<false>(nullptr, ":", &context);
-  if (!pwd.pw_dir)
-    return Error(EINVAL);
-
-  pwd.pw_shell = string_token<false>(nullptr, ":", &context);
-  if (!pwd.pw_shell)
+  size_t len = internal::string_length(line);
+  if (!parse_line(cpp::span<char>(line, len + 1), &pwd))
     return Error(EINVAL);
 
   return pwd;
 }
 
-} // namespace internal
+} // namespace pwd
 
 namespace passwd {
 
-static File *pwd_file = nullptr;
-static const char *pwd_file_path = LIBC_COPT_PWD_FILE_PATH;
+static pwd::FlatFileDatabase<struct passwd> db(LIBC_COPT_PWD_FILE_PATH);
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vonosmas wrote:

I'm wary of static constructors here, as I can imagine `pwd` logic being triggered from some other static constructor in the application logic. I wonder if we can do some form of lazy initialization.

https://github.com/llvm/llvm-project/pull/214720