Import existing toolbox components

1 files changed, 308 insertions, 0 deletions

diff --git a/http_parser.c b/http_parser.c
new file mode 100644
index 0000000..b668a92
--- /dev/null
+++ b/http_parser.c
@@ -0,0 +1,308 @@
+/*
+ * Copyright (C) 2022 Mikhail Burakov. This file is part of toolbox.
+ *
+ * toolbox is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * toolbox is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with toolbox.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "http_parser.h"
+
+#include <stddef.h>
+#include <stdint.h>
+
+#define _(...) __VA_ARGS__
+
+/**
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * |  |.0|.1|.2|.3|.4|.5|.6|.7|.8|.9|.a|.b|.c|.d|.e|.f|
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * |2.|  | !| "| #| $| %| &| '| (| )| *| +| ,| -| .| /|
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * |3.| 0| 1| 2| 3| 4| 5| 6| 7| 8| 9| :| ;| <| =| >| ?|
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * |4.| @| A| B| C| D| E| F| G| H| I| J| K| L| M| N| O|
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * |5.| P| Q| R| S| T| U| V| W| X| Y| Z| [| \| ]| ^| _|
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * |6.| `| a| b| c| d| e| f| g| h| i| j| k| l| m| n| o|
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ * |7.| p| q| r| s| t| u| v| w| x| y| z| {| || }| ~|  |
+ * +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
+ */
+
+// mburakov: RFC9110 5.6.2 Tokens
+static inline _Bool IsTchar(char item) {
+  static const _Bool kAllowed[] = {
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0),
+      _(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0),
+      _(0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1),
+      _(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1),
+      _(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1),
+      _(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+  };
+  return kAllowed[(uint8_t)item];
+}
+
+// mburakov: RFC3986 3.3 Path
+static inline _Bool IsPchar(char item) {
+  static const _Bool kAllowed[] = {
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1),
+      _(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1),
+      _(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1),
+      _(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1),
+      _(0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1),
+      _(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+      _(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0),
+  };
+  return kAllowed[(uint8_t)item];
+}
+
+// mburakov: RFC9110 5.6.3 Whitespace
+static inline _Bool IsOws(char item) {
+  _Bool result = item == ' ' || item == '\t';
+  return result;
+}
+
+// mburakov: RFC9110 5.5 Field Values
+static inline _Bool IsVchar(char item) {
+  uint8_t octet = (uint8_t)item;
+  return octet > ' ' && octet < 0xff;
+}
+
+static enum HttpParser_Result ParseMethod(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user);
+static enum HttpParser_Result ParseTarget(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user);
+static enum HttpParser_Result ParseVersion(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user);
+static enum HttpParser_Result ParseFieldName(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user);
+static enum HttpParser_Result ParseFieldValue(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user);
+
+static enum HttpParser_Result ParseMethod(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user) {
+  (void)callbacks;
+  (void)user;
+  for (const char* data = buffer;;) {
+    if (state->parsing_offset == buffer_size) {
+      return kHttpParser_ResultWantMore;
+    }
+    if (IsTchar(data[state->parsing_offset])) {
+      state->parsing_offset++;
+      continue;
+    }
+    if (data[state->parsing_offset] == ' ') {
+      state->stage = ParseTarget;
+      state->parsing_offset++;
+      state->first_size = state->parsing_offset - 1 - state->first_offset;
+      state->second_offset = state->parsing_offset;
+      return kHttpParser_ResultFinished;
+    }
+    state->stage = 0;
+    return kHttpParser_ResultError;
+  }
+}
+
+static enum HttpParser_Result ParseTarget(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user) {
+  (void)callbacks;
+  (void)user;
+  for (const char* data = buffer;;) {
+    if (state->parsing_offset == buffer_size) {
+      return kHttpParser_ResultWantMore;
+    }
+    if (IsPchar(data[state->parsing_offset])) {
+      state->parsing_offset++;
+      continue;
+    }
+    if (data[state->parsing_offset] == ' ') {
+      state->stage = ParseVersion;
+      state->parsing_offset++;
+      state->second_size = state->parsing_offset - 1 - state->second_offset;
+      state->first_offset = state->parsing_offset;
+      return kHttpParser_ResultFinished;
+    }
+    state->stage = 0;
+    return kHttpParser_ResultError;
+  }
+}
+
+static enum HttpParser_Result ParseVersion(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user) {
+  static const char kReferences[][10] = {
+      {'H', 'T', 'T', 'P', '/', '1', '.', '1', '\r', '\n'},
+      {'H', 'T', 'T', 'P', '/', '1', '.', '0', '\r', '\n'}};
+  for (const char* data = buffer;;) {
+    size_t reference_index = state->parsing_offset - state->first_offset;
+    if (reference_index == sizeof(kReferences[0])) {
+      if (callbacks && callbacks->on_request) {
+        callbacks->on_request(user, buffer, state->first_size,
+                              data + state->second_offset, state->second_size);
+      }
+      state->stage = ParseFieldName;
+      state->first_offset = state->parsing_offset;
+      state->second_size = 0;
+      return kHttpParser_ResultFinished;
+    }
+    if (state->parsing_offset == buffer_size) {
+      return kHttpParser_ResultWantMore;
+    }
+    if (data[state->parsing_offset] == kReferences[0][reference_index] ||
+        data[state->parsing_offset] == kReferences[1][reference_index]) {
+      state->parsing_offset++;
+      continue;
+    }
+    state->stage = 0;
+    return kHttpParser_ResultError;
+  }
+}
+
+static enum HttpParser_Result ParseFieldName(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user) {
+  for (const char* data = buffer;;) {
+    if (state->parsing_offset == buffer_size) {
+      return kHttpParser_ResultWantMore;
+    }
+    if (data[state->parsing_offset] == '\r' &&
+        state->parsing_offset == state->first_offset) {
+      state->maybe_eol = 1;
+      state->parsing_offset++;
+      continue;
+    }
+    if (data[state->parsing_offset] == '\n' &&
+        state->parsing_offset == state->first_offset + 1 && state->maybe_eol) {
+      state->stage = 0;
+      if (callbacks && callbacks->on_finished) {
+        callbacks->on_finished(user, state->parsing_offset + 1);
+      }
+      return kHttpParser_ResultFinished;
+    }
+    if (state->maybe_eol) {
+      state->stage = 0;
+      return kHttpParser_ResultError;
+    }
+    if (IsTchar(data[state->parsing_offset])) {
+      state->parsing_offset++;
+      continue;
+    }
+    if (data[state->parsing_offset] == ':') {
+      state->stage = ParseFieldValue;
+      state->parsing_offset++;
+      state->first_size = state->parsing_offset - 1 - state->first_offset;
+      if (state->first_size) return kHttpParser_ResultFinished;
+    }
+    state->stage = 0;
+    return kHttpParser_ResultError;
+  }
+}
+
+static enum HttpParser_Result ParseFieldValue(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user) {
+  for (const char* data = buffer;;) {
+    if (state->parsing_offset == buffer_size) {
+      return kHttpParser_ResultWantMore;
+    }
+    if (!state->second_size) {
+      if (IsOws(data[state->parsing_offset])) {
+        state->parsing_offset++;
+        continue;
+      }
+      state->second_offset = state->parsing_offset;
+      state->second_size = 0;
+    }
+    if (data[state->parsing_offset] == '\r') {
+      if (!state->second_size) {
+        state->stage = 0;
+        return kHttpParser_ResultError;
+      }
+      state->maybe_eol = 1;
+      state->parsing_offset++;
+      continue;
+    }
+    if (data[state->parsing_offset] == '\n') {
+      if (!state->maybe_eol) {
+        state->stage = 0;
+        return kHttpParser_ResultError;
+      }
+      if (callbacks && callbacks->on_field) {
+        callbacks->on_field(user, data + state->first_offset, state->first_size,
+                            data + state->second_offset, state->second_size);
+      }
+      state->stage = ParseFieldName;
+      state->maybe_eol = 0;
+      state->parsing_offset++;
+      state->first_offset = state->parsing_offset;
+      state->second_size = 0;
+      return kHttpParser_ResultFinished;
+    }
+    if (state->maybe_eol) {
+      state->stage = 0;
+      return kHttpParser_ResultError;
+    }
+    if (IsVchar(data[state->parsing_offset])) {
+      state->parsing_offset++;
+      state->second_size = state->parsing_offset - state->second_offset;
+      continue;
+    }
+    if (IsOws(data[state->parsing_offset])) {
+      state->parsing_offset++;
+      continue;
+    }
+    state->stage = 0;
+    return kHttpParser_ResultError;
+  }
+}
+
+void HttpParser_Reset(struct HttpParser_State* state) {
+  struct HttpParser_State reset = {.stage = ParseMethod};
+  *state = reset;
+}
+
+enum HttpParser_Result HttpParser_Parse(
+    struct HttpParser_State* state, const void* buffer, size_t buffer_size,
+    const struct HttpParser_Callbacks* callbacks, void* user) {
+  enum HttpParser_Result result = kHttpParser_ResultFinished;
+  while (result == kHttpParser_ResultFinished && state->stage)
+    result = (state->stage)(state, buffer, buffer_size, callbacks, user);
+  return result;
+}