implement proper IRQL, DPCs, kernel and user APCs, alertable waits, async file I/O with cancellation, trap frames, selftests, a real driver/device model, native async FAT32, VFAT dotfile fixes, syscall ABI cleanup, async_apc and async_cancel tests, POSIX multi-volume paths, and pimp the readme.

code/posix/posix_path.c

@@ -3,29 +3,36 @@
 #include <string.h>
 #include "posix_path.h"
 
-// The drive letter used as the POSIX filesystem root.
-// A future SYS_GET_BOOT_DRIVE could populate this; hardcoded for v1.
-static const char gRootDrive = '0';
-
 static void FlipSlashes(char* s) {
     for (; *s; s++) if (*s == '/') *s = '\\';
 }
 
+static int IsDriveMount(const char* p) {
+    return p && p[0] == '/' && p[1] >= '0' && p[1] <= '7' &&
+           (p[2] == '\0' || p[2] == '/');
+}
+
 const char* PosixTranslatePath(const char* in, char* out, size_t outSize) {
     if (!in || !out || outSize < 4) return out;
 
-    // Synthetic devices
     if (strcmp(in, "/dev/null") == 0) return SYNTH_DEVNULL;
     if (strcmp(in, "/dev/zero") == 0) return SYNTH_DEVZERO;
 
-    // /proc/self/* - read-only synthesized files; flag with a sentinel so
-    // posix_io.c can intercept them without opening a real file.
-    // (In v1 only /proc/self/pid is handled; others fall through to ENOENT.)
+    if (IsDriveMount(in)) {
+        out[0] = in[1];
+        out[1] = ':';
+        out[2] = '/';
+        const char* rest = (in[2] == '/') ? in + 3 : "";
+        size_t restLen = strlen(rest);
+        if (restLen + 4 > outSize) restLen = outSize - 4;
+        memcpy(out + 3, rest, restLen);
+        out[3 + restLen] = '\0';
+        FlipSlashes(out);
+        return out;
+    }
 
     if (in[0] == '/') {
-        // Absolute POSIX path -> C:\...
-        // outSize must fit "C:\" + rest
-        out[0] = gRootDrive;
+        out[0] = '0';
         out[1] = ':';
         out[2] = '/';
         size_t rest = strlen(in + 1);
@@ -33,7 +40,6 @@ const char* PosixTranslatePath(const char* in, char* out, size_t outSize) {
         memcpy(out + 3, in + 1, rest);
         out[3 + rest] = '\0';
     } else {
-        // Relative - pass through with slash flip only
         size_t len = strlen(in);
         if (len + 1 > outSize) len = outSize - 1;
         memcpy(out, in, len);
@@ -47,16 +53,27 @@ const char* PosixTranslatePath(const char* in, char* out, size_t outSize) {
 void NativeToPosix(const char* in, char* out, size_t outSize) {
     if (!in || !out || outSize == 0) return;
 
-    // Strip "X:\" prefix if present
     const char* src = in;
-    if (src[0] != '\0' && src[1] == ':' && (src[2] == '\\' || src[2] == '/'))
-        src += 2;   // skip "C:", leave the leading backslash
+    char drive = 0;
+    if (src[0] >= '0' && src[0] <= '7' && src[1] == ':' &&
+        (src[2] == '\\' || src[2] == '/')) {
+        drive = src[0];
+        src += 3;
+    }
 
-    size_t len = strlen(src);
-    if (len + 1 > outSize) len = outSize - 1;
-    memcpy(out, src, len);
-    out[len] = '\0';
+    size_t pos = 0;
+    if (drive && drive != '0') {
+        if (outSize < 4) { out[0] = '\0'; return; }
+        out[pos++] = '/';
+        out[pos++] = drive;
+        if (*src) out[pos++] = '/';
+    } else {
+        out[pos++] = '/';
+    }
 
-    // Backslash -> forward slash
-    for (char* p = out; *p; p++) if (*p == '\\') *p = '/';
+    while (*src && pos + 1 < outSize) {
+        out[pos++] = (*src == '\\') ? '/' : *src;
+        src++;
+    }
+    out[pos] = '\0';
 }