Adding upstream version 1:10.11.6.upstream/1%10.11.6upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 688 insertions, 0 deletions

diff --git a/sql/sql_digest.cc b/sql/sql_digest.cc
new file mode 100644
index 00000000..36a6b398
--- /dev/null
+++ b/sql/sql_digest.cc
@@ -0,0 +1,688 @@
+/* Copyright (c) 2008, 2015, Oracle and/or its affiliates. All rights reserved.
+   Copyright (c) 2017, MariaDB Corporation.
+
+  This program 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; version 2 of the License.
+
+  This program 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 this program; if not, write to the Free Software Foundation,
+  51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA */
+
+/*
+  This code needs extra visibility in the lexer structures
+*/
+
+#include "mariadb.h"
+#include "my_md5.h"
+#include "unireg.h"
+
+#include "sql_string.h"
+#include "sql_class.h"
+#include "sql_lex.h"
+#include "sp_pcontext.h"
+#include "sql_digest.h"
+#include "sql_digest_stream.h"
+
+#include "sql_get_diagnostics.h"
+
+/* Generated code */
+#include "yy_mariadb.hh"
+#define LEX_TOKEN_WITH_DEFINITION
+#include "lex_token.h"
+
+/* Name pollution from sql/sql_lex.h */
+#ifdef LEX_YYSTYPE
+#undef LEX_YYSTYPE
+#endif
+
+#define LEX_YYSTYPE YYSTYPE*
+
+#define SIZE_OF_A_TOKEN 2
+
+/**
+  Read a single token from token array.
+*/
+inline uint read_token(const sql_digest_storage *digest_storage,
+                       uint index, uint *tok)
+{
+  uint safe_byte_count= digest_storage->m_byte_count;
+
+  if (index + SIZE_OF_A_TOKEN <= safe_byte_count &&
+      safe_byte_count <= digest_storage->m_token_array_length)
+  {
+    const unsigned char *src= & digest_storage->m_token_array[index];
+    *tok= src[0] | (src[1] << 8);
+    return index + SIZE_OF_A_TOKEN;
+  }
+
+  /* The input byte stream is exhausted. */
+  *tok= 0;
+  return MAX_DIGEST_STORAGE_SIZE + 1;
+}
+
+/**
+  Store a single token in token array.
+*/
+inline void store_token(sql_digest_storage* digest_storage, uint token)
+{
+  DBUG_ASSERT(digest_storage->m_byte_count <= digest_storage->m_token_array_length);
+
+  if (digest_storage->m_byte_count + SIZE_OF_A_TOKEN <= digest_storage->m_token_array_length)
+  {
+    unsigned char* dest= & digest_storage->m_token_array[digest_storage->m_byte_count];
+    dest[0]= token & 0xff;
+    dest[1]= (token >> 8) & 0xff;
+    digest_storage->m_byte_count+= SIZE_OF_A_TOKEN;
+  }
+  else
+  {
+    digest_storage->m_full= true;
+  }
+}
+
+/**
+  Read an identifier from token array.
+*/
+inline uint read_identifier(const sql_digest_storage* digest_storage,
+                            uint index, char ** id_string, int *id_length)
+{
+  uint new_index;
+  uint safe_byte_count= digest_storage->m_byte_count;
+
+  DBUG_ASSERT(index <= safe_byte_count);
+  DBUG_ASSERT(safe_byte_count <= digest_storage->m_token_array_length);
+
+  /*
+    token + length + string are written in an atomic way,
+    so we do always expect a length + string here
+  */
+
+  uint bytes_needed= SIZE_OF_A_TOKEN;
+  /* If we can read token and identifier length */
+  if ((index + bytes_needed) <= safe_byte_count)
+  {
+    const unsigned char *src= & digest_storage->m_token_array[index];
+    /* Read the length of identifier */
+    uint length= src[0] | (src[1] << 8);
+    bytes_needed+= length;
+    /* If we can read entire identifier from token array */
+    if ((index + bytes_needed) <= safe_byte_count)
+    {
+      *id_string= (char *) (src + 2);
+      *id_length= length;
+
+      new_index= index + bytes_needed;
+      DBUG_ASSERT(new_index <= safe_byte_count);
+      return new_index;
+    }
+  }
+
+  /* The input byte stream is exhausted. */
+  return MAX_DIGEST_STORAGE_SIZE + 1;
+}
+
+/**
+  Store an identifier in token array.
+*/
+inline void store_token_identifier(sql_digest_storage* digest_storage,
+                                   uint token,
+                                   size_t id_length, const char *id_name)
+{
+  DBUG_ASSERT(digest_storage->m_byte_count <= digest_storage->m_token_array_length);
+
+  size_t bytes_needed= 2 * SIZE_OF_A_TOKEN + id_length;
+  if (digest_storage->m_byte_count + bytes_needed <= (unsigned int)digest_storage->m_token_array_length)
+  {
+    unsigned char* dest= & digest_storage->m_token_array[digest_storage->m_byte_count];
+    /* Write the token */
+    dest[0]= token & 0xff;
+    dest[1]= (token >> 8) & 0xff;
+    /* Write the string length */
+    dest[2]= id_length & 0xff;
+    dest[3]= (id_length >> 8) & 0xff;
+    /* Write the string data */
+    if (id_length > 0)
+      memcpy((char *)(dest + 4), id_name, id_length);
+    digest_storage->m_byte_count+= (uint)bytes_needed;
+  }
+  else
+  {
+    digest_storage->m_full= true;
+  }
+}
+
+void compute_digest_md5(const sql_digest_storage *digest_storage, unsigned char *md5)
+{
+  compute_md5_hash(md5,
+                   (const char *) digest_storage->m_token_array,
+                   digest_storage->m_byte_count);
+}
+
+/*
+  Iterate token array and updates digest_text.
+*/
+void compute_digest_text(const sql_digest_storage* digest_storage,
+                         String *digest_text)
+{
+  DBUG_ASSERT(digest_storage != NULL);
+  uint byte_count= digest_storage->m_byte_count;
+  String *digest_output= digest_text;
+  uint tok= 0;
+  uint current_byte= 0;
+  lex_token_string *tok_data;
+
+  /* Reset existing data */
+  digest_output->length(0);
+
+  if (byte_count > digest_storage->m_token_array_length)
+  {
+    digest_output->append('\0');
+    return;
+  }
+
+  /* Convert text to utf8 */
+  const CHARSET_INFO *from_cs= get_charset(digest_storage->m_charset_number, MYF(0));
+  const CHARSET_INFO *to_cs= &my_charset_utf8mb3_bin;
+
+  if (from_cs == NULL)
+  {
+    /*
+      Can happen, as we do dirty reads on digest_storage,
+      which can be written to in another thread.
+    */
+    digest_output->append('\0');
+    return;
+  }
+
+  char id_buffer[NAME_LEN + 1]= {'\0'};
+  char *id_string;
+  size_t id_length;
+  bool convert_text= !my_charset_same(from_cs, to_cs);
+
+  while (current_byte < byte_count)
+  {
+    current_byte= read_token(digest_storage, current_byte, &tok);
+
+    if (tok <= 0 || tok >= array_elements(lex_token_array)
+        || current_byte > max_digest_length)
+      return;
+
+    tok_data= &lex_token_array[tok];
+
+    switch (tok)
+    {
+    /* All identifiers are printed with their name. */
+    case IDENT:
+    case IDENT_QUOTED:
+    case TOK_IDENT:
+      {
+        char *id_ptr= NULL;
+        int id_len= 0;
+        uint err_cs= 0;
+
+        /* Get the next identifier from the storage buffer. */
+        current_byte= read_identifier(digest_storage, current_byte,
+                                      &id_ptr, &id_len);
+        if (current_byte > max_digest_length)
+          return;
+
+        if (convert_text)
+        {
+          /* Verify that the converted text will fit. */
+          if (to_cs->mbmaxlen*id_len > NAME_LEN)
+          {
+            digest_output->append("...", 3);
+            break;
+          }
+          /* Convert identifier string into the storage character set. */
+          id_length= my_convert(id_buffer, NAME_LEN, to_cs,
+                                id_ptr, id_len, from_cs, &err_cs);
+          id_string= id_buffer;
+        }
+        else
+        {
+          id_string= id_ptr;
+          id_length= id_len;
+        }
+
+        if (id_length == 0 || err_cs != 0)
+        {
+          break;
+        }
+        /* Copy the converted identifier into the digest string. */
+        digest_output->append('`');
+        if (id_length > 0)
+          digest_output->append(id_string, id_length);
+        digest_output->append("` ", 2);
+      }
+      break;
+
+    /* Everything else is printed as is. */
+    default:
+      /*
+        Make sure not to overflow digest_text buffer.
+        +1 is to make sure extra space for ' '.
+      */
+      int tok_length= tok_data->m_token_length;
+
+      digest_output->append(tok_data->m_token_string, tok_length);
+      if (tok_data->m_append_space)
+        digest_output->append(' ');
+      break;
+    }
+  }
+}
+
+static inline uint peek_token(const sql_digest_storage *digest, uint index)
+{
+  uint token;
+  DBUG_ASSERT(index + SIZE_OF_A_TOKEN <= digest->m_byte_count);
+  DBUG_ASSERT(digest->m_byte_count <=  digest->m_token_array_length);
+
+  token= ((digest->m_token_array[index + 1])<<8) | digest->m_token_array[index];
+  return token;
+}
+
+/**
+  Function to read last two tokens from token array. If an identifier
+  is found, do not look for token before that.
+*/
+static inline void peek_last_two_tokens(const sql_digest_storage* digest_storage,
+                                        uint last_id_index, uint *t1, uint *t2)
+{
+  uint byte_count= digest_storage->m_byte_count;
+  uint peek_index= byte_count;
+
+  if (last_id_index + SIZE_OF_A_TOKEN <= peek_index)
+  {
+    /* Take last token. */
+    peek_index-= SIZE_OF_A_TOKEN;
+    *t1= peek_token(digest_storage, peek_index);
+
+    if (last_id_index + SIZE_OF_A_TOKEN <= peek_index)
+    {
+      /* Take 2nd token from last. */
+      peek_index-= SIZE_OF_A_TOKEN;
+      *t2= peek_token(digest_storage, peek_index);
+    }
+    else
+    {
+      *t2= TOK_UNUSED;
+    }
+  }
+  else
+  {
+    *t1= TOK_UNUSED;
+    *t2= TOK_UNUSED;
+  }
+}
+
+/**
+  Function to read last three tokens from token array. If an identifier
+  is found, do not look for token before that.
+*/
+static inline void peek_last_three_tokens(const sql_digest_storage* digest_storage,
+                                          uint last_id_index, uint *t1, uint *t2, uint *t3)
+{
+  uint byte_count= digest_storage->m_byte_count;
+  uint peek_index= byte_count;
+
+  if (last_id_index + SIZE_OF_A_TOKEN <= peek_index)
+  {
+    /* Take last token. */
+    peek_index-= SIZE_OF_A_TOKEN;
+    *t1= peek_token(digest_storage, peek_index);
+
+    if (last_id_index + SIZE_OF_A_TOKEN <= peek_index)
+    {
+      /* Take 2nd token from last. */
+      peek_index-= SIZE_OF_A_TOKEN;
+      *t2= peek_token(digest_storage, peek_index);
+
+      if (last_id_index + SIZE_OF_A_TOKEN <= peek_index)
+      {
+        /* Take 3rd token from last. */
+        peek_index-= SIZE_OF_A_TOKEN;
+        *t3= peek_token(digest_storage, peek_index);
+      }
+      else
+      {
+        *t3= TOK_UNUSED;
+      }
+    }
+    else
+    {
+      *t2= TOK_UNUSED;
+      *t3= TOK_UNUSED;
+    }
+  }
+  else
+  {
+    *t1= TOK_UNUSED;
+    *t2= TOK_UNUSED;
+    *t3= TOK_UNUSED;
+  }
+}
+
+sql_digest_state* digest_add_token(sql_digest_state *state,
+                                   uint token,
+                                   LEX_YYSTYPE yylval)
+{
+  sql_digest_storage *digest_storage= NULL;
+
+  digest_storage= &state->m_digest_storage;
+
+  /*
+    Stop collecting further tokens if digest storage is full or
+    if END token is received.
+  */
+  if (digest_storage->m_full || token == END_OF_INPUT)
+    return NULL;
+
+  /*
+    Take last_token 2 tokens collected till now. These tokens will be used
+    in reduce for normalisation. Make sure not to consider ID tokens in reduce.
+  */
+  uint last_token;
+  uint last_token2;
+
+  switch (token)
+  {
+    case NUM:
+    case LONG_NUM:
+    case ULONGLONG_NUM:
+    case DECIMAL_NUM:
+    case FLOAT_NUM:
+    case BIN_NUM:
+    case HEX_NUM:
+    {
+      bool found_unary;
+      do
+      {
+        found_unary= false;
+        peek_last_two_tokens(digest_storage, state->m_last_id_index,
+                             &last_token, &last_token2);
+
+        if ((last_token == '-') || (last_token == '+'))
+        {
+          /*
+            We need to differentiate:
+            - a <unary minus> operator
+            - a <unary plus> operator
+            from
+            - a <binary minus> operator
+            - a <binary plus> operator
+            to only reduce "a = -1" to "a = ?", and not change "b - 1" to "b ?"
+
+            Binary operators are found inside an expression,
+            while unary operators are found at the beginning of an expression, or after operators.
+
+            To achieve this, every token that is followed by an <expr> expression
+            in the SQL grammar is flagged.
+            See sql/sql_yacc.yy
+            See sql/gen_lex_token.cc
+
+            For example,
+            "(-1)" is parsed as "(", "-", NUM, ")", and lex_token_array["("].m_start_expr is true,
+            so reduction of the "-" NUM is done, the result is "(?)".
+            "(a-1)" is parsed as "(", ID, "-", NUM, ")", and lex_token_array[ID].m_start_expr is false,
+            so the operator is binary, no reduction is done, and the result is "(a-?)".
+          */
+          if (lex_token_array[last_token2].m_start_expr)
+          {
+            /*
+              REDUCE:
+              TOK_GENERIC_VALUE := (UNARY_PLUS | UNARY_MINUS) (NUM | LOG_NUM | ... | FLOAT_NUM)
+
+              REDUCE:
+              TOK_GENERIC_VALUE := (UNARY_PLUS | UNARY_MINUS) TOK_GENERIC_VALUE
+            */
+            token= TOK_GENERIC_VALUE;
+            digest_storage->m_byte_count-= SIZE_OF_A_TOKEN;
+            found_unary= true;
+          }
+        }
+      } while (found_unary);
+    }
+    /* for case NULL_SYM below */
+    /* fall through */
+    case LEX_HOSTNAME:
+    case TEXT_STRING:
+    case NCHAR_STRING:
+    case PARAM_MARKER:
+    {
+      /*
+        REDUCE:
+        TOK_GENERIC_VALUE := BIN_NUM | DECIMAL_NUM | ... | ULONGLONG_NUM
+      */
+      token= TOK_GENERIC_VALUE;
+
+      peek_last_two_tokens(digest_storage, state->m_last_id_index,
+                           &last_token, &last_token2);
+
+      if ((last_token2 == TOK_GENERIC_VALUE ||
+           last_token2 == TOK_GENERIC_VALUE_LIST) &&
+          (last_token == ','))
+      {
+        /*
+          REDUCE:
+          TOK_GENERIC_VALUE_LIST :=
+            TOK_GENERIC_VALUE ',' TOK_GENERIC_VALUE
+
+          REDUCE:
+          TOK_GENERIC_VALUE_LIST :=
+            TOK_GENERIC_VALUE_LIST ',' TOK_GENERIC_VALUE
+        */
+        digest_storage->m_byte_count-= 2*SIZE_OF_A_TOKEN;
+        token= TOK_GENERIC_VALUE_LIST;
+      }
+      /*
+        Add this token or the resulting reduce to digest storage.
+      */
+      store_token(digest_storage, token);
+      break;
+    }
+    case ')':
+    {
+      peek_last_two_tokens(digest_storage, state->m_last_id_index,
+                           &last_token, &last_token2);
+
+      if (last_token == TOK_GENERIC_VALUE &&
+          last_token2 == '(')
+      {
+        /*
+          REDUCE:
+          TOK_ROW_SINGLE_VALUE :=
+            '(' TOK_GENERIC_VALUE ')'
+        */
+        digest_storage->m_byte_count-= 2*SIZE_OF_A_TOKEN;
+        token= TOK_ROW_SINGLE_VALUE;
+
+        /* Read last two tokens again */
+        peek_last_two_tokens(digest_storage, state->m_last_id_index,
+                             &last_token, &last_token2);
+
+        if ((last_token2 == TOK_ROW_SINGLE_VALUE ||
+             last_token2 == TOK_ROW_SINGLE_VALUE_LIST) &&
+            (last_token == ','))
+        {
+          /*
+            REDUCE:
+            TOK_ROW_SINGLE_VALUE_LIST :=
+              TOK_ROW_SINGLE_VALUE ',' TOK_ROW_SINGLE_VALUE
+
+            REDUCE:
+            TOK_ROW_SINGLE_VALUE_LIST :=
+              TOK_ROW_SINGLE_VALUE_LIST ',' TOK_ROW_SINGLE_VALUE
+          */
+          digest_storage->m_byte_count-= 2*SIZE_OF_A_TOKEN;
+          token= TOK_ROW_SINGLE_VALUE_LIST;
+        }
+      }
+      else if (last_token == TOK_GENERIC_VALUE_LIST &&
+               last_token2 == '(')
+      {
+        /*
+          REDUCE:
+          TOK_ROW_MULTIPLE_VALUE :=
+            '(' TOK_GENERIC_VALUE_LIST ')'
+        */
+        digest_storage->m_byte_count-= 2*SIZE_OF_A_TOKEN;
+        token= TOK_ROW_MULTIPLE_VALUE;
+
+        /* Read last two tokens again */
+        peek_last_two_tokens(digest_storage, state->m_last_id_index,
+                             &last_token, &last_token2);
+
+        if ((last_token2 == TOK_ROW_MULTIPLE_VALUE ||
+             last_token2 == TOK_ROW_MULTIPLE_VALUE_LIST) &&
+            (last_token == ','))
+        {
+          /*
+            REDUCE:
+            TOK_ROW_MULTIPLE_VALUE_LIST :=
+              TOK_ROW_MULTIPLE_VALUE ',' TOK_ROW_MULTIPLE_VALUE
+
+            REDUCE:
+            TOK_ROW_MULTIPLE_VALUE_LIST :=
+              TOK_ROW_MULTIPLE_VALUE_LIST ',' TOK_ROW_MULTIPLE_VALUE
+          */
+          digest_storage->m_byte_count-= 2*SIZE_OF_A_TOKEN;
+          token= TOK_ROW_MULTIPLE_VALUE_LIST;
+        }
+      }
+      /*
+        Add this token or the resulting reduce to digest storage.
+      */
+      store_token(digest_storage, token);
+      break;
+    }
+    case IDENT:
+    case IDENT_QUOTED:
+    {
+      YYSTYPE *lex_token= yylval;
+      const char *yytext= lex_token->lex_str.str;
+      size_t yylen= lex_token->lex_str.length;
+
+      /*
+        REDUCE:
+          TOK_IDENT := IDENT | IDENT_QUOTED
+        The parser gives IDENT or IDENT_TOKEN for the same text,
+        depending on the character set used.
+        We unify both to always print the same digest text,
+        and always have the same digest hash.
+      */
+      token= TOK_IDENT;
+      /* Add this token and identifier string to digest storage. */
+      store_token_identifier(digest_storage, token, yylen, yytext);
+
+      /* Update the index of last identifier found. */
+      state->m_last_id_index= digest_storage->m_byte_count;
+      break;
+    }
+    default:
+    {
+      /* Add this token to digest storage. */
+      store_token(digest_storage, token);
+      break;
+    }
+  }
+
+  return state;
+}
+
+sql_digest_state* digest_reduce_token(sql_digest_state *state,
+                                      uint token_left, uint token_right)
+{
+  sql_digest_storage *digest_storage= NULL;
+
+  digest_storage= &state->m_digest_storage;
+
+  /*
+    Stop collecting further tokens if digest storage is full.
+  */
+  if (digest_storage->m_full)
+    return NULL;
+
+  uint last_token;
+  uint last_token2;
+  uint last_token3;
+  uint token_to_push= TOK_UNUSED;
+
+  peek_last_two_tokens(digest_storage, state->m_last_id_index,
+                       &last_token, &last_token2);
+
+  /*
+    There is only one caller of digest_reduce_token(),
+    see sql/sql_yacc.yy, rule literal := NULL_SYM.
+    REDUCE:
+      token_left := token_right
+    Used for:
+      TOK_GENERIC_VALUE := NULL_SYM
+  */
+
+  if (last_token == token_right)
+  {
+    /*
+      Current stream is like:
+        TOKEN_X TOKEN_RIGHT .
+      REDUCE to
+        TOKEN_X TOKEN_LEFT .
+    */
+    digest_storage->m_byte_count-= SIZE_OF_A_TOKEN;
+    store_token(digest_storage, token_left);
+  }
+  else
+  {
+    /*
+      Current stream is like:
+        TOKEN_X TOKEN_RIGHT TOKEN_Y .
+      Pop TOKEN_Y
+        TOKEN_X TOKEN_RIGHT . TOKEN_Y
+      REDUCE to
+        TOKEN_X TOKEN_LEFT . TOKEN_Y
+    */
+    DBUG_ASSERT(last_token2 == token_right);
+    digest_storage->m_byte_count-= 2 * SIZE_OF_A_TOKEN;
+    store_token(digest_storage, token_left);
+    token_to_push= last_token;
+  }
+
+  peek_last_three_tokens(digest_storage, state->m_last_id_index,
+                         &last_token, &last_token2, &last_token3);
+
+  if ((last_token3 == TOK_GENERIC_VALUE ||
+       last_token3 == TOK_GENERIC_VALUE_LIST) &&
+      (last_token2 == ',') &&
+      (last_token == TOK_GENERIC_VALUE))
+  {
+    /*
+      REDUCE:
+      TOK_GENERIC_VALUE_LIST :=
+        TOK_GENERIC_VALUE ',' TOK_GENERIC_VALUE
+
+      REDUCE:
+      TOK_GENERIC_VALUE_LIST :=
+        TOK_GENERIC_VALUE_LIST ',' TOK_GENERIC_VALUE
+    */
+    digest_storage->m_byte_count-= 3*SIZE_OF_A_TOKEN;
+    store_token(digest_storage, TOK_GENERIC_VALUE_LIST);
+  }
+
+  if (token_to_push != TOK_UNUSED)
+  {
+    /*
+      Push TOKEN_Y
+    */
+    store_token(digest_storage, token_to_push);
+  }
+
+  return state;
+}
+