Add some sample requirement implementation comments to where.c.

FossilOrigin-Name: 9854ad00aed08793ae7ba3c2cfbab7a2dba4dcb8

2 files changed, 12 insertions, 399 deletions

diff --git a/src/test_md5.c b/src/test_md5.c
deleted file mode 100644
index 4253933e0..000000000
--- a/src/test_md5.c
+++ /dev/null
@@ -1,395 +0,0 @@
-/*
-** SQLite uses this code for testing only.  It is not a part of
-** the SQLite library.  This file implements two new TCL commands
-** "md5" and "md5file" that compute md5 checksums on arbitrary text
-** and on complete files.  These commands are used by the "testfixture"
-** program to help verify the correct operation of the SQLite library.
-**
-** The original use of these TCL commands was to test the ROLLBACK
-** feature of SQLite.  First compute the MD5-checksum of the database.
-** Then make some changes but rollback the changes rather than commit
-** them.  Compute a second MD5-checksum of the file and verify that the
-** two checksums are the same.  Such is the original use of this code.
-** New uses may have been added since this comment was written.
-**
-** $Id: test_md5.c,v 1.10 2009/02/03 19:52:59 shane Exp $
-*/
-/*
- * This code implements the MD5 message-digest algorithm.
- * The algorithm is due to Ron Rivest.  This code was
- * written by Colin Plumb in 1993, no copyright is claimed.
- * This code is in the public domain; do with it what you wish.
- *
- * Equivalent code is available from RSA Data Security, Inc.
- * This code has been tested against that, and is equivalent,
- * except that you don't need to include two pages of legalese
- * with every copy.
- *
- * To compute the message digest of a chunk of bytes, declare an
- * MD5Context structure, pass it to MD5Init, call MD5Update as
- * needed on buffers full of bytes, and then call MD5Final, which
- * will fill a supplied 16-byte array with the digest.
- */
-#include <tcl.h>
-#include <string.h>
-#include "sqlite3.h"
-
-/*
- * If compiled on a machine that doesn't have a 32-bit integer,
- * you just set "uint32" to the appropriate datatype for an
- * unsigned 32-bit integer.  For example:
- *
- *       cc -Duint32='unsigned long' md5.c
- *
- */
-#ifndef uint32
-#  define uint32 unsigned int
-#endif
-
-struct Context {
-  int isInit;
-  uint32 buf[4];
-  uint32 bits[2];
-  unsigned char in[64];
-};
-typedef struct Context MD5Context;
-
-/*
- * Note: this code is harmless on little-endian machines.
- */
-static void byteReverse (unsigned char *buf, unsigned longs){
-        uint32 t;
-        do {
-                t = (uint32)((unsigned)buf[3]<<8 | buf[2]) << 16 |
-                            ((unsigned)buf[1]<<8 | buf[0]);
-                *(uint32 *)buf = t;
-                buf += 4;
-        } while (--longs);
-}
-/* The four core functions - F1 is optimized somewhat */
-
-/* #define F1(x, y, z) (x & y | ~x & z) */
-#define F1(x, y, z) (z ^ (x & (y ^ z)))
-#define F2(x, y, z) F1(z, x, y)
-#define F3(x, y, z) (x ^ y ^ z)
-#define F4(x, y, z) (y ^ (x | ~z))
-
-/* This is the central step in the MD5 algorithm. */
-#define MD5STEP(f, w, x, y, z, data, s) \
-        ( w += f(x, y, z) + data,  w = w<<s | w>>(32-s),  w += x )
-
-/*
- * The core of the MD5 algorithm, this alters an existing MD5 hash to
- * reflect the addition of 16 longwords of new data.  MD5Update blocks
- * the data and converts bytes into longwords for this routine.
- */
-static void MD5Transform(uint32 buf[4], const uint32 in[16]){
-        register uint32 a, b, c, d;
-
-        a = buf[0];
-        b = buf[1];
-        c = buf[2];
-        d = buf[3];
-
-        MD5STEP(F1, a, b, c, d, in[ 0]+0xd76aa478,  7);
-        MD5STEP(F1, d, a, b, c, in[ 1]+0xe8c7b756, 12);
-        MD5STEP(F1, c, d, a, b, in[ 2]+0x242070db, 17);
-        MD5STEP(F1, b, c, d, a, in[ 3]+0xc1bdceee, 22);
-        MD5STEP(F1, a, b, c, d, in[ 4]+0xf57c0faf,  7);
-        MD5STEP(F1, d, a, b, c, in[ 5]+0x4787c62a, 12);
-        MD5STEP(F1, c, d, a, b, in[ 6]+0xa8304613, 17);
-        MD5STEP(F1, b, c, d, a, in[ 7]+0xfd469501, 22);
-        MD5STEP(F1, a, b, c, d, in[ 8]+0x698098d8,  7);
-        MD5STEP(F1, d, a, b, c, in[ 9]+0x8b44f7af, 12);
-        MD5STEP(F1, c, d, a, b, in[10]+0xffff5bb1, 17);
-        MD5STEP(F1, b, c, d, a, in[11]+0x895cd7be, 22);
-        MD5STEP(F1, a, b, c, d, in[12]+0x6b901122,  7);
-        MD5STEP(F1, d, a, b, c, in[13]+0xfd987193, 12);
-        MD5STEP(F1, c, d, a, b, in[14]+0xa679438e, 17);
-        MD5STEP(F1, b, c, d, a, in[15]+0x49b40821, 22);
-
-        MD5STEP(F2, a, b, c, d, in[ 1]+0xf61e2562,  5);
-        MD5STEP(F2, d, a, b, c, in[ 6]+0xc040b340,  9);
-        MD5STEP(F2, c, d, a, b, in[11]+0x265e5a51, 14);
-        MD5STEP(F2, b, c, d, a, in[ 0]+0xe9b6c7aa, 20);
-        MD5STEP(F2, a, b, c, d, in[ 5]+0xd62f105d,  5);
-        MD5STEP(F2, d, a, b, c, in[10]+0x02441453,  9);
-        MD5STEP(F2, c, d, a, b, in[15]+0xd8a1e681, 14);
-        MD5STEP(F2, b, c, d, a, in[ 4]+0xe7d3fbc8, 20);
-        MD5STEP(F2, a, b, c, d, in[ 9]+0x21e1cde6,  5);
-        MD5STEP(F2, d, a, b, c, in[14]+0xc33707d6,  9);
-        MD5STEP(F2, c, d, a, b, in[ 3]+0xf4d50d87, 14);
-        MD5STEP(F2, b, c, d, a, in[ 8]+0x455a14ed, 20);
-        MD5STEP(F2, a, b, c, d, in[13]+0xa9e3e905,  5);
-        MD5STEP(F2, d, a, b, c, in[ 2]+0xfcefa3f8,  9);
-        MD5STEP(F2, c, d, a, b, in[ 7]+0x676f02d9, 14);
-        MD5STEP(F2, b, c, d, a, in[12]+0x8d2a4c8a, 20);
-
-        MD5STEP(F3, a, b, c, d, in[ 5]+0xfffa3942,  4);
-        MD5STEP(F3, d, a, b, c, in[ 8]+0x8771f681, 11);
-        MD5STEP(F3, c, d, a, b, in[11]+0x6d9d6122, 16);
-        MD5STEP(F3, b, c, d, a, in[14]+0xfde5380c, 23);
-        MD5STEP(F3, a, b, c, d, in[ 1]+0xa4beea44,  4);
-        MD5STEP(F3, d, a, b, c, in[ 4]+0x4bdecfa9, 11);
-        MD5STEP(F3, c, d, a, b, in[ 7]+0xf6bb4b60, 16);
-        MD5STEP(F3, b, c, d, a, in[10]+0xbebfbc70, 23);
-        MD5STEP(F3, a, b, c, d, in[13]+0x289b7ec6,  4);
-        MD5STEP(F3, d, a, b, c, in[ 0]+0xeaa127fa, 11);
-        MD5STEP(F3, c, d, a, b, in[ 3]+0xd4ef3085, 16);
-        MD5STEP(F3, b, c, d, a, in[ 6]+0x04881d05, 23);
-        MD5STEP(F3, a, b, c, d, in[ 9]+0xd9d4d039,  4);
-        MD5STEP(F3, d, a, b, c, in[12]+0xe6db99e5, 11);
-        MD5STEP(F3, c, d, a, b, in[15]+0x1fa27cf8, 16);
-        MD5STEP(F3, b, c, d, a, in[ 2]+0xc4ac5665, 23);
-
-        MD5STEP(F4, a, b, c, d, in[ 0]+0xf4292244,  6);
-        MD5STEP(F4, d, a, b, c, in[ 7]+0x432aff97, 10);
-        MD5STEP(F4, c, d, a, b, in[14]+0xab9423a7, 15);
-        MD5STEP(F4, b, c, d, a, in[ 5]+0xfc93a039, 21);
-        MD5STEP(F4, a, b, c, d, in[12]+0x655b59c3,  6);
-        MD5STEP(F4, d, a, b, c, in[ 3]+0x8f0ccc92, 10);
-        MD5STEP(F4, c, d, a, b, in[10]+0xffeff47d, 15);
-        MD5STEP(F4, b, c, d, a, in[ 1]+0x85845dd1, 21);
-        MD5STEP(F4, a, b, c, d, in[ 8]+0x6fa87e4f,  6);
-        MD5STEP(F4, d, a, b, c, in[15]+0xfe2ce6e0, 10);
-        MD5STEP(F4, c, d, a, b, in[ 6]+0xa3014314, 15);
-        MD5STEP(F4, b, c, d, a, in[13]+0x4e0811a1, 21);
-        MD5STEP(F4, a, b, c, d, in[ 4]+0xf7537e82,  6);
-        MD5STEP(F4, d, a, b, c, in[11]+0xbd3af235, 10);
-        MD5STEP(F4, c, d, a, b, in[ 2]+0x2ad7d2bb, 15);
-        MD5STEP(F4, b, c, d, a, in[ 9]+0xeb86d391, 21);
-
-        buf[0] += a;
-        buf[1] += b;
-        buf[2] += c;
-        buf[3] += d;
-}
-
-/*
- * Start MD5 accumulation.  Set bit count to 0 and buffer to mysterious
- * initialization constants.
- */
-static void MD5Init(MD5Context *ctx){
-        ctx->isInit = 1;
-        ctx->buf[0] = 0x67452301;
-        ctx->buf[1] = 0xefcdab89;
-        ctx->buf[2] = 0x98badcfe;
-        ctx->buf[3] = 0x10325476;
-        ctx->bits[0] = 0;
-        ctx->bits[1] = 0;
-}
-
-/*
- * Update context to reflect the concatenation of another buffer full
- * of bytes.
- */
-static 
-void MD5Update(MD5Context *pCtx, const unsigned char *buf, unsigned int len){
-        struct Context *ctx = (struct Context *)pCtx;
-        uint32 t;
-
-        /* Update bitcount */
-
-        t = ctx->bits[0];
-        if ((ctx->bits[0] = t + ((uint32)len << 3)) < t)
-                ctx->bits[1]++; /* Carry from low to high */
-        ctx->bits[1] += len >> 29;
-
-        t = (t >> 3) & 0x3f;    /* Bytes already in shsInfo->data */
-
-        /* Handle any leading odd-sized chunks */
-
-        if ( t ) {
-                unsigned char *p = (unsigned char *)ctx->in + t;
-
-                t = 64-t;
-                if (len < t) {
-                        memcpy(p, buf, len);
-                        return;
-                }
-                memcpy(p, buf, t);
-                byteReverse(ctx->in, 16);
-                MD5Transform(ctx->buf, (uint32 *)ctx->in);
-                buf += t;
-                len -= t;
-        }
-
-        /* Process data in 64-byte chunks */
-
-        while (len >= 64) {
-                memcpy(ctx->in, buf, 64);
-                byteReverse(ctx->in, 16);
-                MD5Transform(ctx->buf, (uint32 *)ctx->in);
-                buf += 64;
-                len -= 64;
-        }
-
-        /* Handle any remaining bytes of data. */
-
-        memcpy(ctx->in, buf, len);
-}
-
-/*
- * Final wrapup - pad to 64-byte boundary with the bit pattern 
- * 1 0* (64-bit count of bits processed, MSB-first)
- */
-static void MD5Final(unsigned char digest[16], MD5Context *pCtx){
-        struct Context *ctx = (struct Context *)pCtx;
-        unsigned count;
-        unsigned char *p;
-
-        /* Compute number of bytes mod 64 */
-        count = (ctx->bits[0] >> 3) & 0x3F;
-
-        /* Set the first char of padding to 0x80.  This is safe since there is
-           always at least one byte free */
-        p = ctx->in + count;
-        *p++ = 0x80;
-
-        /* Bytes of padding needed to make 64 bytes */
-        count = 64 - 1 - count;
-
-        /* Pad out to 56 mod 64 */
-        if (count < 8) {
-                /* Two lots of padding:  Pad the first block to 64 bytes */
-                memset(p, 0, count);
-                byteReverse(ctx->in, 16);
-                MD5Transform(ctx->buf, (uint32 *)ctx->in);
-
-                /* Now fill the next block with 56 bytes */
-                memset(ctx->in, 0, 56);
-        } else {
-                /* Pad block to 56 bytes */
-                memset(p, 0, count-8);
-        }
-        byteReverse(ctx->in, 14);
-
-        /* Append length in bits and transform */
-        ((uint32 *)ctx->in)[ 14 ] = ctx->bits[0];
-        ((uint32 *)ctx->in)[ 15 ] = ctx->bits[1];
-
-        MD5Transform(ctx->buf, (uint32 *)ctx->in);
-        byteReverse((unsigned char *)ctx->buf, 4);
-        memcpy(digest, ctx->buf, 16);
-        memset(ctx, 0, sizeof(ctx));    /* In case it is sensitive */
-}
-
-/*
-** Convert a digest into base-16.  digest should be declared as
-** "unsigned char digest[16]" in the calling function.  The MD5
-** digest is stored in the first 16 bytes.  zBuf should
-** be "char zBuf[33]".
-*/
-static void DigestToBase16(unsigned char *digest, char *zBuf){
-  static char const zEncode[] = "0123456789abcdef";
-  int i, j;
-
-  for(j=i=0; i<16; i++){
-    int a = digest[i];
-    zBuf[j++] = zEncode[(a>>4)&0xf];
-    zBuf[j++] = zEncode[a & 0xf];
-  }
-  zBuf[j] = 0;
-}
-
-/*
-** A TCL command for md5.  The argument is the text to be hashed.  The
-** Result is the hash in base64.  
-*/
-static int md5_cmd(void*cd, Tcl_Interp *interp, int argc, const char **argv){
-  MD5Context ctx;
-  unsigned char digest[16];
-  char zBuf[33];
-
-  if( argc!=2 ){
-    Tcl_AppendResult(interp,"wrong # args: should be \"", argv[0], 
-        " TEXT\"", 0);
-    return TCL_ERROR;
-  }
-  MD5Init(&ctx);
-  MD5Update(&ctx, (unsigned char*)argv[1], (unsigned)strlen(argv[1]));
-  MD5Final(digest, &ctx);
-  DigestToBase16(digest, zBuf);
-  Tcl_AppendResult(interp, zBuf, (char*)0);
-  return TCL_OK;
-}
-
-/*
-** A TCL command to take the md5 hash of a file.  The argument is the
-** name of the file.
-*/
-static int md5file_cmd(void*cd, Tcl_Interp*interp, int argc, const char **argv){
-  FILE *in;
-  MD5Context ctx;
-  unsigned char digest[16];
-  char zBuf[10240];
-
-  if( argc!=2 ){
-    Tcl_AppendResult(interp,"wrong # args: should be \"", argv[0], 
-        " FILENAME\"", 0);
-    return TCL_ERROR;
-  }
-  in = fopen(argv[1],"rb");
-  if( in==0 ){
-    Tcl_AppendResult(interp,"unable to open file \"", argv[1], 
-         "\" for reading", 0);
-    return TCL_ERROR;
-  }
-  MD5Init(&ctx);
-  for(;;){
-    int n;
-    n = fread(zBuf, 1, sizeof(zBuf), in);
-    if( n<=0 ) break;
-    MD5Update(&ctx, (unsigned char*)zBuf, (unsigned)n);
-  }
-  fclose(in);
-  MD5Final(digest, &ctx);
-  DigestToBase16(digest, zBuf);
-  Tcl_AppendResult(interp, zBuf, (char*)0);
-  return TCL_OK;
-}
-
-/*
-** Register the two TCL commands above with the TCL interpreter.
-*/
-int Md5_Init(Tcl_Interp *interp){
-  Tcl_CreateCommand(interp, "md5", (Tcl_CmdProc*)md5_cmd, 0, 0);
-  Tcl_CreateCommand(interp, "md5file", (Tcl_CmdProc*)md5file_cmd, 0, 0);
-  return TCL_OK;
-}
-
-/*
-** During testing, the special md5sum() aggregate function is available.
-** inside SQLite.  The following routines implement that function.
-*/
-static void md5step(sqlite3_context *context, int argc, sqlite3_value **argv){
-  MD5Context *p;
-  int i;
-  if( argc<1 ) return;
-  p = sqlite3_aggregate_context(context, sizeof(*p));
-  if( p==0 ) return;
-  if( !p->isInit ){
-    MD5Init(p);
-  }
-  for(i=0; i<argc; i++){
-    const char *zData = (char*)sqlite3_value_text(argv[i]);
-    if( zData ){
-      MD5Update(p, (unsigned char*)zData, strlen(zData));
-    }
-  }
-}
-static void md5finalize(sqlite3_context *context){
-  MD5Context *p;
-  unsigned char digest[16];
-  char zBuf[33];
-  p = sqlite3_aggregate_context(context, sizeof(*p));
-  MD5Final(digest,p);
-  DigestToBase16(digest, zBuf);
-  sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
-}
-int Md5_Register(sqlite3 *db){
-  int rc = sqlite3_create_function(db, "md5sum", -1, SQLITE_UTF8, 0, 0, 
-                                 md5step, md5finalize);
-  sqlite3_overload_function(db, "md5sum", -1);  /* To exercise this API */
-  return rc;
-}
diff --git a/src/where.c b/src/where.c
index 15a17b7a7..70642fc5b 100644
--- a/src/where.c
+++ b/src/where.c
@@ -648,17 +648,25 @@ static int isLikeOrGlob(
 #endif
   pList = pExpr->x.pList;
   pLeft = pList->a[1].pExpr;
-  if( pLeft->op!=TK_COLUMN ){
+  if( pLeft->op!=TK_COLUMN || sqlite3ExprAffinity(pLeft)!=SQLITE_AFF_TEXT ){
+    /* IMP: R-02065-49465 The left-hand side of the LIKE or GLOB operator must
+    ** be the name of an indexed column with TEXT affinity. */
     return 0;
   }
+  assert( pLeft->iColumn!=(-1) ); /* Because IPK never has AFF_TEXT */
   pColl = sqlite3ExprCollSeq(pParse, pLeft);
-  assert( pColl!=0 || pLeft->iColumn==-1 );
-  if( pColl==0 ) return 0;
+  assert( pColl!=0 );  /* Every non-IPK column has a collating sequence */
   if( (pColl->type!=SQLITE_COLL_BINARY || *pnoCase) &&
       (pColl->type!=SQLITE_COLL_NOCASE || !*pnoCase) ){
+    /* IMP: R-09003-32046 For the GLOB operator, the column must use the
+    ** default BINARY collating sequence.
+    ** IMP: R-41408-28306 For the LIKE operator, if case_sensitive_like mode
+    ** is enabled then the column must use the default BINARY collating
+    ** sequence, or if case_sensitive_like mode is disabled then the column
+    ** must use the built-in NOCASE collating sequence.
+    */
     return 0;
   }
-  if( sqlite3ExprAffinity(pLeft)!=SQLITE_AFF_TEXT ) return 0;
 
   pRight = pList->a[0].pExpr;
   op = pRight->op;