diff --git a/src/libutil/file-descriptor.hh b/src/libutil/file-descriptor.hh index b54bab83c..710efaf1d 100644 --- a/src/libutil/file-descriptor.hh +++ b/src/libutil/file-descriptor.hh @@ -77,8 +77,13 @@ void writeFull(Descriptor fd, std::string_view s, bool allowInterrupts = true); /** * Read a line from a file descriptor. + * + * @param fd The file descriptor to read from + * @param eofOk If true, return an unterminated line if EOF is reached. (e.g. the empty string) + * + * @return A line of text ending in `\n`, or a string without `\n` if `eofOk` is true and EOF is reached. */ -std::string readLine(Descriptor fd); +std::string readLine(Descriptor fd, bool eofOk = false); /** * Write a line to a file descriptor. diff --git a/src/libutil/unix/file-descriptor.cc b/src/libutil/unix/file-descriptor.cc index 2c1126e09..ac7c086af 100644 --- a/src/libutil/unix/file-descriptor.cc +++ b/src/libutil/unix/file-descriptor.cc @@ -47,7 +47,7 @@ void writeFull(int fd, std::string_view s, bool allowInterrupts) } -std::string readLine(int fd) +std::string readLine(int fd, bool eofOk) { std::string s; while (1) { @@ -58,8 +58,12 @@ std::string readLine(int fd) if (rd == -1) { if (errno != EINTR) throw SysError("reading a line"); - } else if (rd == 0) - throw EndOfFile("unexpected EOF reading a line"); + } else if (rd == 0) { + if (eofOk) + return s; + else + throw EndOfFile("unexpected EOF reading a line"); + } else { if (ch == '\n') return s; s += ch;