* Get rid of the substitutes database table (NIX-47). Instead, if we

  need any info on substitutable paths, we just call the substituters
  (such as download-using-manifests.pl) directly.  This means that
  it's no longer necessary for nix-pull to register substitutes or for
  nix-channel to clear them, which makes those operations much faster
  (NIX-95).  Also, we don't have to worry about keeping nix-pull
  manifests (in /nix/var/nix/manifests) and the database in sync with
  each other.

  The downside is that there is some overhead in calling an external
  program to get the substitutes info.  For instance, "nix-env -qas"
  takes a bit longer.

  Abolishing the substitutes table also makes the logic in
  local-store.cc simpler, as we don't need to store info for invalid
  paths.  On the downside, you cannot do things like "nix-store -qR"
  on a substitutable but invalid path (but nobody did that anyway).

* Never catch interrupts (the Interrupted exception).

1 files changed, 5 insertions, 2 deletions

diff --git a/src/libutil/util.cc b/src/libutil/util.cc
index d61b35bdfbe0..edfd26b0b739 100644
--- a/src/libutil/util.cc
+++ b/src/libutil/util.cc
@@ -23,13 +23,13 @@ extern char * * environ;
 namespace nix {
 
 
-Error::Error(const format & f)
+BaseError::BaseError(const format & f)
 {
     err = f.str();
 }
 
 
-Error & Error::addPrefix(const format & f)
+BaseError & BaseError::addPrefix(const format & f)
 {
     err = f.str() + err;
     return *this;
@@ -491,6 +491,7 @@ string drainFD(int fd)
     string result;
     unsigned char buffer[4096];
     while (1) {
+        checkInterrupt();
         ssize_t rd = read(fd, buffer, sizeof buffer);
         if (rd == -1) {
             if (errno != EINTR)
@@ -775,6 +776,8 @@ void killUser(uid_t uid)
 
 string runProgram(Path program, bool searchPath, const Strings & args)
 {
+    checkInterrupt();
+    
     /* Create a pipe. */
     Pipe pipe;
     pipe.create();