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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 14:07:11 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 14:07:11 +0000
commit63847496f14c813a5d80efd5b7de0f1294ffe1e3 (patch)
tree01c7571c7c762ceee70638549a99834fdd7c411b /ext/misc/uint.c
parentInitial commit. (diff)
downloadsqlite3-63847496f14c813a5d80efd5b7de0f1294ffe1e3.tar.xz
sqlite3-63847496f14c813a5d80efd5b7de0f1294ffe1e3.zip
Adding upstream version 3.45.1.upstream/3.45.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'ext/misc/uint.c')
-rw-r--r--ext/misc/uint.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/ext/misc/uint.c b/ext/misc/uint.c
new file mode 100644
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--- /dev/null
+++ b/ext/misc/uint.c
@@ -0,0 +1,92 @@
+/*
+** 2020-04-14
+**
+** The author disclaims copyright to this source code. In place of
+** a legal notice, here is a blessing:
+**
+** May you do good and not evil.
+** May you find forgiveness for yourself and forgive others.
+** May you share freely, never taking more than you give.
+**
+******************************************************************************
+**
+** This SQLite extension implements the UINT collating sequence.
+**
+** UINT works like BINARY for text, except that embedded strings
+** of digits compare in numeric order.
+**
+** * Leading zeros are handled properly, in the sense that
+** they do not mess of the maginitude comparison of embedded
+** strings of digits. "x00123y" is equal to "x123y".
+**
+** * Only unsigned integers are recognized. Plus and minus
+** signs are ignored. Decimal points and exponential notation
+** are ignored.
+**
+** * Embedded integers can be of arbitrary length. Comparison
+** is *not* limited integers that can be expressed as a
+** 64-bit machine integer.
+*/
+#include "sqlite3ext.h"
+SQLITE_EXTENSION_INIT1
+#include <assert.h>
+#include <string.h>
+#include <ctype.h>
+
+/*
+** Compare text in lexicographic order, except strings of digits
+** compare in numeric order.
+*/
+static int uintCollFunc(
+ void *notUsed,
+ int nKey1, const void *pKey1,
+ int nKey2, const void *pKey2
+){
+ const unsigned char *zA = (const unsigned char*)pKey1;
+ const unsigned char *zB = (const unsigned char*)pKey2;
+ int i=0, j=0, x;
+ (void)notUsed;
+ while( i<nKey1 && j<nKey2 ){
+ x = zA[i] - zB[j];
+ if( isdigit(zA[i]) ){
+ int k;
+ if( !isdigit(zB[j]) ) return x;
+ while( i<nKey1 && zA[i]=='0' ){ i++; }
+ while( j<nKey2 && zB[j]=='0' ){ j++; }
+ k = 0;
+ while( i+k<nKey1 && isdigit(zA[i+k])
+ && j+k<nKey2 && isdigit(zB[j+k]) ){
+ k++;
+ }
+ if( i+k<nKey1 && isdigit(zA[i+k]) ){
+ return +1;
+ }else if( j+k<nKey2 && isdigit(zB[j+k]) ){
+ return -1;
+ }else{
+ x = memcmp(zA+i, zB+j, k);
+ if( x ) return x;
+ i += k;
+ j += k;
+ }
+ }else if( x ){
+ return x;
+ }else{
+ i++;
+ j++;
+ }
+ }
+ return (nKey1 - i) - (nKey2 - j);
+}
+
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int sqlite3_uint_init(
+ sqlite3 *db,
+ char **pzErrMsg,
+ const sqlite3_api_routines *pApi
+){
+ SQLITE_EXTENSION_INIT2(pApi);
+ (void)pzErrMsg; /* Unused parameter */
+ return sqlite3_create_collation(db, "uint", SQLITE_UTF8, 0, uintCollFunc);
+}