1 files changed, 74 insertions, 0 deletions

diff --git a/pathexec_env.c b/pathexec_env.c
new file mode 100644
index 0000000..1305469
--- /dev/null
+++ b/pathexec_env.c
@@ -0,0 +1,74 @@
+/* Public domain. */
+
+#include "stralloc.h"
+#include "alloc.h"
+#include "str.h"
+#include "byte.h"
+#include "env.h"
+#include "pathexec.h"
+
+static stralloc plus;
+static stralloc tmp;
+
+int pathexec_env(const char *s,const char *t)
+{
+  if (!s) return 1;
+  if (!stralloc_copys(&tmp,s)) return 0;
+  if (t) {
+    if (!stralloc_cats(&tmp,"=")) return 0;
+    if (!stralloc_cats(&tmp,t)) return 0;
+  }
+  if (!stralloc_0(&tmp)) return 0;
+  return stralloc_cat(&plus,&tmp);
+}
+
+void pathexec_env_run(const char *file, const char *const *argv)
+{
+  const char **e;
+  unsigned int elen;
+  unsigned int i;
+  unsigned int j;
+  unsigned int split;
+  unsigned int t;
+
+  if (!stralloc_cats(&plus,"")) return;
+
+  elen = 0;
+  for (i = 0;environ[i];++i)
+    ++elen;
+  for (i = 0;i < plus.len;++i)
+    if (!plus.s[i])
+      ++elen;
+
+  e = (const char **) alloc((elen + 1) * sizeof(char *));
+  if (!e) return;
+
+  elen = 0;
+  for (i = 0;environ[i];++i)
+    e[elen++] = environ[i];
+
+  j = 0;
+  for (i = 0;i < plus.len;++i)
+    if (!plus.s[i]) {
+      split = str_chr(plus.s + j,'=');
+      for (t = 0;t < elen;++t)
+        if (byte_equal(plus.s + j,split,e[t]))
+          if (e[t][split] == '=') {
+            --elen;
+            e[t] = e[elen];
+            break;
+          }
+      if (plus.s[j + split])
+        e[elen++] = plus.s + j;
+      j = i + 1;
+    }
+  e[elen] = 0;
+
+  pathexec_run(file,argv,e);
+  alloc_free(e);
+}
+
+void pathexec(const char *const *argv)
+{
+  return pathexec_env_run(*argv, argv);
+}