feat: ports - git port

2026-08-09 10:47:07 +02:00
parent cfb8d91442
commit 6f3cf99667
34 changed files with 2255 additions and 2 deletions
@@ -0,0 +1,57 @@
+compat/ -- what MontaukOS does not have, and what git gets instead.
+
+Two kinds of file live here.
+
+HEADER OVERLAYS use #include_next to pull in the Montauk libc's own header
+and then add what git needs on top. They are found first because -I compat
+precedes the libc include path.
+
+    unistd.h      identity (getuid/geteuid/...), symlink/readlink/link,
+                  chown, fsync, process groups, execl/execlp, getpass, alarm
+    signal.h      the sigaction() family and NSIG
+    time.h        localtime_r/gmtime_r/ctime_r/asctime_r
+    sys/stat.h    S_ISUID/S_ISGID/S_ISVTX and the S_IF* type constants
+    sys/time.h    ITIMER_* selectors
+    sys/types.h   the BSD aliases (u_char, u_int, ...) the ISC-derived
+                  inet_ntop/inet_pton want
+
+STANDALONE HEADERS are for things the libc has no header for at all:
+
+    poll.h        struct pollfd; the implementation reports everything ready
+    pwd.h         struct passwd, answered from the session user
+    grp.h         struct group; every lookup fails (no group database)
+    termios.h     accepted and ignored; there is no line discipline
+    netdb.h       resolver types; every lookup fails
+    syslog.h      discards (only `git daemon` logs, and it is not built)
+    sys/socket.h  BSD socket API; every call fails with ENOSYS
+    sys/un.h      struct sockaddr_un, for the type only
+    sys/ioctl.h   TIOCGWINSZ, which IS implemented (SYS_TERMSIZE)
+    sys/utsname.h uname(), static MontaukOS strings
+    sys/resource.h getrlimit says "unlimited"; getrusage fails
+    sys/statvfs.h  fails; no filesystem statistics syscall
+    netinet/in.h, netinet/tcp.h, arpa/inet.h  address types and byte order
+
+THESE FILES ARE NOT SHIMS. They are the port's own code:
+
+    montauk-paths.h   force-included into every translation unit, ahead of
+                      git-compat-util.h, so git recognises "0:/path" as an
+                      absolute path. Without it git treats every MontaukOS
+                      absolute path as relative and prepends the cwd to it.
+    montauk-ownership.h  also force-included: answers git's safe.directory
+                      "is this repository mine?" check with yes. MontaukOS
+                      stores no per-file owner, so the default lstat-vs-geteuid
+                      comparison is false for every directory on the system.
+                      Read the header before changing it -- it says what this
+                      gives up once the OS grows real ownership.
+    montauk-init.h    declares montauk_startup(), called from main() by the
+                      patch series.
+
+    montauk-compat.c  the implementations, each commented with what it
+                      really does. Built into libgitcompat.a, which sits on
+                      the link line ahead of liblibc.a.
+
+THE RULE followed throughout: a shim either does the real thing, or fails
+with an errno git already knows how to report. Nothing silently pretends to
+have done work it did not do -- with one deliberate exception, fsync(),
+which reports success because git treats a failed fsync as fatal and would
+abort every commit. That one is called out at its definition.