Reinstall keeps drivers with the assign; wifipi uses the canonical extension header

cmake/check-anxs2ext-abi.cmake

@@ -9,6 +9,7 @@
 # made of its own code bytes, and on a PiStorm32 A1200 neither card came up.
 # This compiles a call through each typedef with the tree's flags and stops
 # the configure unless the caller pops what it pushed: 8, 16 and 4 bytes.
+# It also pins the record's offsets, which no version from MIN on may move.
 #
 # SPDX-License-Identifier: MIT
 
@@ -19,7 +20,18 @@ endif()
 set(_s2x_dir "${CMAKE_BINARY_DIR}/check-anxs2ext-abi")
 file(MAKE_DIRECTORY "${_s2x_dir}")
 file(WRITE "${_s2x_dir}/probe.c" [=[
+#include <stddef.h>
 #include <aminetxduo/anxs2ext.h>
+/* The record's prefix is the same at every version from MIN on: a driver
+   accepting [MIN, VERSION] reads these offsets whichever one it is handed. */
+_Static_assert(offsetof(AnxdS2Extension, Version)  ==  0, "Version");
+_Static_assert(offsetof(AnxdS2Extension, Size)     ==  2, "Size");
+_Static_assert(offsetof(AnxdS2Extension, Request)  ==  4, "Request");
+_Static_assert(offsetof(AnxdS2Extension, Accepted) ==  8, "Accepted");
+_Static_assert(offsetof(AnxdS2Extension, RxDirect) == 12, "RxDirect");
+_Static_assert(offsetof(AnxdS2Extension, RxFilled) == 16, "RxFilled");
+_Static_assert(offsetof(AnxdS2Extension, TxFlags)  == 20, "TxFlags");
+_Static_assert(sizeof(AnxdS2Extension)             == 24, "size");
 UBYTE *probe_rx_direct(AnxdS2RxDirect f, APTR io, ULONG len)
 {
     return f(io, len) + 1;

install/Install-AmiNetXDuo

@@ -2350,6 +2350,33 @@
       (safe))
   ))
 
+; A KEPT FILE FOLLOWS THE ASSIGN TOO.  One written before the drawer named
+; its drivers through AmiNetXDuo: says DEVICE=SYS:AmiNetXDuo/Devs/Networks/...
+; and would go on opening that drawer's drivers under a library from wherever
+; the assign points next.  The Installer cannot read the line, so
+; InstallSameFile rewrites it: only a DEVICE line naming one of our drivers
+; in this drawer, or the one the assign still names, and only its value.
+; Another driver, or one of ours elsewhere, is the user's choice and stays.
+(if (AND KEEP_OLD DRAWER_LAYOUT)
+    (foreach D_IFDIR "~(#?.info)"
+      (if (< @each-type 0)
+        (
+          (set KEPT_IF (tackon D_IFDIR @each-name))
+          (if (<> 0
+                  (run ("\"%s\" \"%s\" \"%s\" \"%s\" DEVICES"
+                        S_SAMEFILE KEPT_IF (tackon D_DEVS "Networks")
+                        "AmiNetXDuo:Devs/Networks")
+                       (prompt "Pointing the kept configuration at this "
+                               "drawer's drivers")
+                       (help "A kept interface file that names a driver "
+                             "of this drawer by its full path is changed to "
+                             "name it through AmiNetXDuo:.  Nothing else in "
+                             "the file changes.")))
+              (message
+                "\"" KEPT_IF "\" could not be updated.  If its DEVICE line "
+                "names a driver by this drawer's full path, change it to "
+                "AmiNetXDuo:Devs/Networks/ followed by the driver's name."))))))
+
 ; --- the netdb files, only where there is nothing already ----------------
 ;
 ; A machine that has had Roadshow or AmiTCP on it already has these, very

src/tools/CMakeLists.txt

@@ -227,7 +227,7 @@ aminetxduo_add_tool(tool_addnetinterface AddNetInterface
 # object; dos.library can.  The archive keeps this beside the Installer and
 # does not copy it into C:.
 aminetxduo_add_tool(tool_installsamefile InstallSameFile
-    SOURCES installsamefile.c)
+    SOURCES installsamefile.c devicehome.c)
 
 # The other Installer-only primitive: identify Emu68's supported on-board
 # network devices from its device tree without opening either device.
@@ -910,6 +910,16 @@ if(NOT CMAKE_CROSSCOMPILING)
     target_compile_options(test_netprefs_text PRIVATE -Wall -Wextra)
     set_target_properties(test_netprefs_text PROPERTIES C_STANDARD 11)
 
+    # A kept interface file's DEVICE line follows the AmiNetXDuo: assign
+    # (InstallSameFile DEVICES): only our drivers in this drawer move.
+    add_executable(test_devicehome
+        test/test_devicehome.c
+        devicehome.c)
+    target_include_directories(test_devicehome PRIVATE
+        "${CMAKE_CURRENT_SOURCE_DIR}")
+    target_compile_options(test_devicehome PRIVATE -Wall -Wextra)
+    set_target_properties(test_devicehome PROPERTIES C_STANDARD 11)
+
     # NetPrefs lays itself out from the gadget font's metrics.  Every page at
     # topaz 8, 11, a proportional 13 and a wide 15 keeps labels off borders
     # and gadgets apart; a font too wide for 640 reports that it does not fit.
@@ -1149,6 +1159,7 @@ if(NOT CMAKE_CROSSCOMPILING)
     add_test(NAME fetchurl_rfc3986 COMMAND test_fetchurl)
     add_test(NAME toolsock_connect_budget COMMAND test_toolbudget)
     add_test(NAME netprefs_preserves_text COMMAND test_netprefs_text)
+    add_test(NAME devicehome_rewrites_only_ours COMMAND test_devicehome)
     add_test(NAME netprefs_font_layout COMMAND test_netprefs_layout)
     add_test(NAME httpframe_bodies COMMAND test_httpframe)
     add_test(NAME httplock_rfc4918 COMMAND test_httplock)

src/tools/devicehome.c

@@ -0,0 +1,139 @@
+/* SPDX-License-Identifier: MIT */
+#include "devicehome.h"
+
+/* Every driver an install writes into its Devs/Networks. */
+static const char *const dh_drivers[] =
+{
+    "anxnet.device",
+    "anxgenet.device",
+    "anxwifipi.device",
+    "anxzz9000.device",
+};
+
+#define DH_DRIVERS (sizeof(dh_drivers) / sizeof(dh_drivers[0]))
+
+static size_t dh_len(const char *s)
+{
+    size_t n = 0;
+    while (s[n] != '\0') n++;
+    return n;
+}
+
+static char dh_lower(char c)
+{
+    return (c >= 'A' && c <= 'Z') ? (char)(c + 32) : c;
+}
+
+/* AmigaDOS names compare without case. */
+static int dh_equal(const char *a, size_t alen, const char *b)
+{
+    size_t i;
+    for (i = 0; i < alen; i++)
+        if (b[i] == '\0' || dh_lower(a[i]) != dh_lower(b[i])) return 0;
+    return b[alen] == '\0';
+}
+
+int dh_absolute_driver(const char *value, size_t len, char *dir,
+                       size_t dir_cap, const char **driver)
+{
+    size_t colon = 0, base = 0, dir_len, i, d;
+
+    while (colon < len && value[colon] != ':') colon++;
+    /* No volume (":Devs/..." is the current one), or the assign itself. */
+    if (colon == 0 || colon >= len || dh_equal(value, colon, "AmiNetXDuo"))
+        return 0;
+    for (i = colon; i < len; i++)
+        if (value[i] == ':' || value[i] == '/') base = i + 1;
+
+    for (d = 0; d < DH_DRIVERS; d++)
+        if (dh_equal(value + base, len - base, dh_drivers[d])) break;
+    if (d == DH_DRIVERS)
+        return 0;
+
+    dir_len = (value[base - 1] == '/') ? base - 1 : base;
+    if (dir_len + 1 > dir_cap)
+        return 0;
+    for (i = 0; i < dir_len; i++) dir[i] = value[i];
+    dir[dir_len] = '\0';
+    *driver = dh_drivers[d];
+    return 1;
+}
+
+static int dh_put(char *out, size_t cap, size_t *used, const char *s, size_t n)
+{
+    size_t i;
+    if (n > cap - *used) return 0;
+    for (i = 0; i < n; i++) out[(*used)++] = s[i];
+    return 1;
+}
+
+/* The value of a DEVICE line, as src/config/config_text.c reads it: "DEVICE",
+   optional '=', then one token or a quoted string.  A quoted value with an
+   AmigaDOS '*' escape is not offered: its bytes are not the name. */
+static int dh_device_value(const char *line, size_t len, size_t *vbeg,
+                           size_t *vend)
+{
+    size_t p = 0, k;
+
+    while (p < len && (line[p] == ' ' || line[p] == '\t')) p++;
+    k = p;
+    while (p < len && line[p] != '=' && line[p] != ' ' && line[p] != '\t' &&
+           line[p] != '\r')
+        p++;
+    if (!dh_equal(line + k, p - k, "device")) return 0;
+    while (p < len && (line[p] == ' ' || line[p] == '\t')) p++;
+    if (p < len && line[p] == '=') p++;
+    while (p < len && (line[p] == ' ' || line[p] == '\t')) p++;
+
+    if (p < len && line[p] == '"')
+    {
+        *vbeg = ++p;
+        while (p < len && line[p] != '"')
+            if (line[p++] == '*') return 0;
+        if (p >= len) return 0;
+    }
+    else
+    {
+        *vbeg = p;
+        while (p < len && line[p] != ' ' && line[p] != '\t' && line[p] != '\r' &&
+               line[p] != '#' && line[p] != ';')
+            p++;
+    }
+    *vend = p;
+    return p > *vbeg;
+}
+
+long dh_rehome(const char *old, size_t oldlen, char *out, size_t cap,
+               size_t *newlen, DhOursFn ours, void *ctx)
+{
+    size_t at = 0, used = 0;
+    long   rewritten = 0;
+
+    while (at < oldlen)
+    {
+        size_t end = at, vbeg, vend;
+        char   dir[128];
+        const char *driver;
+
+        while (end < oldlen && old[end] != '\n') end++;
+        if (dh_device_value(old + at, end - at, &vbeg, &vend) &&
+            dh_absolute_driver(old + at + vbeg, vend - vbeg, dir, sizeof(dir),
+                               &driver) &&
+            ours(dir, ctx))
+        {
+            if (!dh_put(out, cap, &used, old + at, vbeg) ||
+                !dh_put(out, cap, &used, DH_ASSIGN_NETWORKS "/",
+                        sizeof(DH_ASSIGN_NETWORKS "/") - 1) ||
+                !dh_put(out, cap, &used, driver, dh_len(driver)))
+                return -1;
+            at += vend;
+            rewritten++;
+        }
+        if (end < oldlen) end++;
+        if (!dh_put(out, cap, &used, old + at, end - at))
+            return -1;
+        at = end;
+    }
+    *newlen = used;
+    return rewritten;
+}

src/tools/devicehome.h

@@ -0,0 +1,28 @@
+/* Where an interface file's DEVICE= finds one of this stack's drivers.  Pure
+   text, used by InstallSameFile and tested on the host (test_devicehome). */
+#ifndef AMINETXDUO_DEVICEHOME_H
+#define AMINETXDUO_DEVICEHOME_H
+
+#include <stddef.h>
+
+/* The drawer layout's own name for its drivers. */
+#define DH_ASSIGN_NETWORKS "AmiNetXDuo:Devs/Networks"
+
+/* For a DEVICE value naming one of OUR drivers by an absolute path that does
+   not go through the AmiNetXDuo: assign: returns 1, the directory part in
+   dir (NUL-terminated; "Vol:" or "Vol:a/b") and the driver's own name.
+   Returns 0 for anything else, including a dir that does not fit. */
+int dh_absolute_driver(const char *value, size_t len, char *dir,
+                       size_t dir_cap, const char **driver);
+
+/* Asked for each candidate directory: nonzero when it is this drawer's. */
+typedef int (*DhOursFn)(const char *dir, void *ctx);
+
+/* Copy old to out, replacing the value of every DEVICE line that
+   dh_absolute_driver() accepts and ours() claims by
+   AmiNetXDuo:Devs/Networks/<driver>.  Every other byte is kept.  Returns the
+   number of lines rewritten, or -1 when out is too small. */
+long dh_rehome(const char *old, size_t oldlen, char *out, size_t cap,
+               size_t *newlen, DhOursFn ours, void *ctx);
+
+#endif