1 files changed, 148 insertions, 0 deletions
diff --git a/ext/lsm1/lsm_str.c b/ext/lsm1/lsm_str.c
new file mode 100644
index 0000000..9b1b63c
--- /dev/null
+++ b/ext/lsm1/lsm_str.c
@@ -0,0 +1,148 @@
+/*
+** 2012-04-27
+**
+** 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.
+**
+*************************************************************************
+**
+** Dynamic string functions.
+*/
+#include "lsmInt.h"
+
+/*
+** Turn bulk and uninitialized memory into an LsmString object
+*/
+void lsmStringInit(LsmString *pStr, lsm_env *pEnv){
+  memset(pStr, 0, sizeof(pStr[0]));
+  pStr->pEnv = pEnv;
+}
+
+/*
+** Increase the memory allocated for holding the string.  Realloc as needed.
+**
+** If a memory allocation error occurs, set pStr->n to -1 and free the existing
+** allocation.  If a prior memory allocation has occurred, this routine is a
+** no-op.
+*/
+int lsmStringExtend(LsmString *pStr, int nNew){
+  assert( nNew>0 );
+  if( pStr->n<0 ) return LSM_NOMEM;
+  if( pStr->n + nNew >= pStr->nAlloc ){
+    int nAlloc = pStr->n + nNew + 100;
+    char *zNew = lsmRealloc(pStr->pEnv, pStr->z, nAlloc);
+    if( zNew==0 ){
+      lsmFree(pStr->pEnv, pStr->z);
+      nAlloc = 0;
+      pStr->n = -1;
+    }
+    pStr->nAlloc = nAlloc;
+    pStr->z = zNew;
+  }
+  return (pStr->z ? LSM_OK : LSM_NOMEM_BKPT);
+}
+
+/*
+** Clear an LsmString object, releasing any allocated memory that it holds.
+** This also clears the error indication (if any).
+*/
+void lsmStringClear(LsmString *pStr){
+  lsmFree(pStr->pEnv, pStr->z);
+  lsmStringInit(pStr, pStr->pEnv);
+}
+
+/*
+** Append N bytes of text to the end of an LsmString object.  If
+** N is negative, append the entire string.
+**
+** If the string is in an error state, this routine is a no-op.
+*/
+int lsmStringAppend(LsmString *pStr, const char *z, int N){
+  int rc;
+  if( N<0 ) N = (int)strlen(z);
+  rc = lsmStringExtend(pStr, N+1);
+  if( pStr->nAlloc ){
+    memcpy(pStr->z+pStr->n, z, N+1);
+    pStr->n += N;
+  }
+  return rc;
+}
+
+int lsmStringBinAppend(LsmString *pStr, const u8 *a, int n){
+  int rc;
+  rc = lsmStringExtend(pStr, n);
+  if( pStr->nAlloc ){
+    memcpy(pStr->z+pStr->n, a, n);
+    pStr->n += n;
+  }
+  return rc;
+}
+
+/*
+** Append printf-formatted content to an LsmString.
+*/
+void lsmStringVAppendf(
+  LsmString *pStr, 
+  const char *zFormat, 
+  va_list ap1,
+  va_list ap2
+){
+#if (!defined(__STDC_VERSION__) || (__STDC_VERSION__<199901L)) && \
+    !defined(__APPLE__)
+  extern int vsnprintf(char *str, size_t size, const char *format, va_list ap)
+    /* Compatibility crutch for C89 compilation mode. sqlite3_vsnprintf()
+       does not work identically and causes test failures if used here.
+       For the time being we are assuming that the target has vsnprintf(),
+       but that is not guaranteed to be the case for pure C89 platforms.
+    */;
+#endif
+  int nWrite;
+  int nAvail;
+
+  nAvail = pStr->nAlloc - pStr->n;
+  nWrite = vsnprintf(pStr->z + pStr->n, nAvail, zFormat, ap1);
+
+  if( nWrite>=nAvail ){
+    lsmStringExtend(pStr, nWrite+1);
+    if( pStr->nAlloc==0 ) return;
+    nWrite = vsnprintf(pStr->z + pStr->n, nWrite+1, zFormat, ap2);
+  }
+
+  pStr->n += nWrite;
+  pStr->z[pStr->n] = 0;
+}
+
+void lsmStringAppendf(LsmString *pStr, const char *zFormat, ...){
+  va_list ap, ap2;
+  va_start(ap, zFormat);
+  va_start(ap2, zFormat);
+  lsmStringVAppendf(pStr, zFormat, ap, ap2);
+  va_end(ap);
+  va_end(ap2);
+}
+
+int lsmStrlen(const char *zName){
+  int nRet = 0;
+  while( zName[nRet] ) nRet++;
+  return nRet;
+}
+
+/*
+** Write into memory obtained from lsm_malloc().
+*/
+char *lsmMallocPrintf(lsm_env *pEnv, const char *zFormat, ...){
+  LsmString s;
+  va_list ap, ap2;
+  lsmStringInit(&s, pEnv);
+  va_start(ap, zFormat);
+  va_start(ap2, zFormat);
+  lsmStringVAppendf(&s, zFormat, ap, ap2);
+  va_end(ap);
+  va_end(ap2);
+  if( s.n<0 ) return 0;
+  return (char *)lsmReallocOrFree(pEnv, s.z, s.n+1);
+}