Native Client side changes for debugging support: stdout/err -> postmessage.

src/trusted/service_runtime/nacl_resource.c

+/*
+ * Copyright (c) 2011 The Native Client Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <string.h>
+
+#include "native_client/src/trusted/service_runtime/nacl_resource.h"
+
+#include "native_client/src/include/nacl_base.h"
+#include "native_client/src/include/nacl_macros.h"
+#include "native_client/src/shared/platform/nacl_check.h"
+#include "native_client/src/shared/platform/nacl_log.h"
+#include "native_client/src/trusted/desc/nacl_desc_base.h"
+#include "native_client/src/trusted/desc/nacl_desc_io.h"
+#include "native_client/src/trusted/service_runtime/include/sys/fcntl.h"
+#include "native_client/src/trusted/service_runtime/nacl_desc_postmessage.h"
+#include "native_client/src/trusted/service_runtime/sel_ldr.h"
+
+struct NaClDesc *NaClResourceOpen(struct NaClResource *self,
+                                  char const          *resource_locator,
+                                  int                 nacl_flags,
+                                  int                 mode) {
+  size_t  ix;
+  size_t  default_ix = ~(size_t) 0;  /* greater than self->num_schemes */
+  size_t  prefix_len;
+  int     allow_debug = 0;
+
+  NaClLog(4, "NaClResourceOpen(*,\"%s\",0x%x,0x%x)\n",
+          resource_locator, nacl_flags, mode);
+  prefix_len = strlen(NACL_RESOURCE_DEBUG_WARNING);
+  if (strncmp(resource_locator, NACL_RESOURCE_DEBUG_WARNING,
+              prefix_len) == 0) {
+    allow_debug = 1;
+    resource_locator += prefix_len;
+  }
+
+  for (ix = 0; ix < self->num_schemes; ++ix) {
+    if (self->schemes[ix].default_scheme) {
+      default_ix = ix;
+    }
+    prefix_len = strlen(self->schemes[ix].scheme_prefix);
+    NaClLog(4, " prefix \"%s\"\n", self->schemes[ix].scheme_prefix);
+    if (0 == strncmp(self->schemes[ix].scheme_prefix, resource_locator,
+                     prefix_len)) {
+      char const *rest = resource_locator + prefix_len;
+      NaClLog(4, " prefix match at %"NACL_PRIuS", rest \"%s\".\n", ix, rest);
+      return (*self->schemes[ix].Open)(self, rest,
+                                       nacl_flags, mode, allow_debug);
+    }
+  }
+  if (default_ix < self->num_schemes) {
+    NaClLog(4, " trying default scheme %"NACL_PRIuS".\n", default_ix);
+    return (*self->schemes[default_ix].Open)(self, resource_locator,
+                                             nacl_flags, mode, allow_debug);
+  }
+  return NULL;
+}
+
+int NaClResourceCtor(struct NaClResource              *self,
+                     struct NaClResourceSchemes const *scheme_tbl,
+                     size_t                           num_schemes) {
+  self->schemes = scheme_tbl;
+  self->num_schemes = num_schemes;
+  return 1;
+}
+
+/* --------------------------------------------------------------------------
+ *
+ * Subclass of NaClResource
+ *
+ * --------------------------------------------------------------------------
+ */
+
+int NaClResourceNaClAppCtor(struct NaClResourceNaClApp        *self,
+                            struct NaClResourceSchemes const  *scheme_tbl,
+                            size_t                            num_schemes,
+                            struct NaClApp                    *nap) {
+  NaClLog(4,
+          ("NaClResourceNaClAppCtor, scheme_tbl 0x%"NACL_PRIxPTR","
+           " size %"NACL_PRIuS".\n"),
+          (uintptr_t) scheme_tbl, num_schemes);
+  if (!NaClResourceCtor(&self->base, scheme_tbl, num_schemes)) {
+    return 0;
+  }
+  self->nap = nap;
+  return 1;
+}
+
+static struct NaClDesc *NaClResourceNaClAppFileOpen(
+    struct NaClResource *vself,
+    char const          *resource_locator,
+    int                 nacl_flags,
+    int                 mode,
+    int                 allow_debug) {
+  struct NaClResourceNaClApp  *self = (struct NaClResourceNaClApp *) vself;
+  struct NaClHostDesc         *hd = NULL;
+  struct NaClDescIoDesc       *did = NULL;
+  struct NaClDesc             *rv = NULL;
+
+  /*
+   * Functionality-wise, we're startup phase-independent; we can
+   * always try to open a file; however, initialization requires that
+   * file opens occur only early, in NACl_RESOURCE_PHASE_START.
+   */
+  UNREFERENCED_PARAMETER(allow_debug);
+  if (self->nap->resource_phase != NACL_RESOURCE_PHASE_START) {
+    return NULL;
+  }
+  hd = malloc(sizeof *hd);
+  did = malloc(sizeof *did);
+  if (NULL == hd || NULL == did) {
+    goto done;
+  }
+  if (!NaClHostDescOpen(hd, resource_locator, nacl_flags, mode)) {
+    goto done;
+  }
+  if (!NaClDescIoDescCtor(did, hd)) {
+    (void) NaClHostDescClose(hd);
+    goto done;
+  }
+  hd = NULL;  /* ownership passed into did */
+  rv = (struct NaClDesc *) did;  /* success */
+  did = NULL;
+ done:
+  free(hd);
+  free(did);
+  return rv;
+}
+
+/*
+ * We don't bother to make it a singleton postmessage device.  Thread
+ * safety is handled when the device object gets the lock to use the
+ * reverse channel.
+ */
+static struct NaClDesc *NaClResourceNaClAppDevOpen(
+    struct NaClResource *vself,
+    char const          *resource_locator,
+    int                 nacl_flags,
+    int                 mode,
+    int                 allow_debug) {
+  struct NaClResourceNaClApp  *self = (struct NaClResourceNaClApp *) vself;
+  struct NaClDescPostMessage  *ndpm = NULL;
+
+  if (self->nap->resource_phase != NACL_RESOURCE_PHASE_REV_CHAN
+      || !allow_debug) {
+    return NULL;
+  }
+
+  if (0 == strcmp(resource_locator, NACL_RESOURCE_DEV_POSTMESSAGE_LOCATOR)) {
+    /* disallow O_RDONLY or O_RDWR */
+    if ((NACL_ABI_O_ACCMODE & nacl_flags) != NACL_ABI_O_WRONLY) {
+      return NULL;
+    }
+    /* allow O_CREAT, O_APPEND, and O_TRUNC */
+    UNREFERENCED_PARAMETER(mode);  /* ignored; O_CREAT doesn't create. */
+
+    ndpm = malloc(sizeof *ndpm);
+    CHECK(NULL != ndpm);
+    CHECK(NaClDescPostMessageCtor(ndpm, self->nap));
+  }
+  return (struct NaClDesc *) ndpm;
+}
+
+int NaClResourceNaClAppInit(struct NaClResourceNaClApp  *rp,
+                            struct NaClApp              *nap) {
+  static struct NaClResourceSchemes const schemes[] = {
+    {
+      NACL_RESOURCE_FILE_PREFIX,
+      1,  /* default scheme */
+      NaClResourceNaClAppFileOpen,
+    }, {
+      NACL_RESOURCE_DEV_PREFIX,
+      0,  /* not default scheme */
+      NaClResourceNaClAppDevOpen,
+    },
+  };
+
+  NaClLog(4, "NaClResourceNaClAppInit -- Ctor with default schemes\n");
+  return NaClResourceNaClAppCtor(rp, schemes, NACL_ARRAY_SIZE(schemes), nap);
+}