Complete revamp of the pathexec functions

- pathexec_run is now called exec_ae
    a for provided file name (default: argv[0])
    e for provided envp (default: environ)
- pathexec is now called mexec. m for merge environment. Option letters are:
    a for provided file name (default: argv[0])
    e for provided envp (default: environ)
    f for provided envp *and* length of the envp
    m for provided modif string plus its length (the length is always needed
because the modifs are null-terminated)
    n for provided modif string, length *and* number of modifs
- functions have a foo0 version for _exit(0) when argv[0] is null
- functions have a xfoo version to die if the exec fails
- and a xfoo0
- Compatibility #defines and #includes are there until the next major bump

1 files changed, 19 insertions, 0 deletions

diff --git a/src/libenvexec/env_addmodif.c b/src/libenvexec/env_addmodif.c
new file mode 100644
index 0000000..ddd1be3
--- /dev/null
+++ b/src/libenvexec/env_addmodif.c
@@ -0,0 +1,19 @@
+/* ISC license. */
+
+#include <sys/types.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/env.h>
+
+int env_addmodif (stralloc *sa, char const *s, char const *t)
+{
+  size_t oldlen = sa->len ;
+  if (!s) return 1 ;
+  if (!stralloc_cats(sa, s)) return 0 ;
+  if ((t && (!stralloc_catb(sa, "=", 1) || !stralloc_cats(sa, t)))
+   || !stralloc_0(sa))
+  {
+    sa->len = oldlen ;
+    return 0 ;
+  }
+  return 1 ;
+}