shell.c

SQLite 2.8.6 源代码,用来在Linux/Unix/Windows上编译安装.它是一个小型的数据库,但是非常好用,速度也快,一般的数据库查询之类的操作据统计比MySQL,PostgreSQL

/*
** 2001 September 15
**
** 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 file contains code to implement the "sqlite" command line
** utility for accessing SQLite databases.
**
** $Id: shell.c,v 1.82 2003/07/18 01:30:59 drh Exp $
*/
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include "sqlite.h"
#include <ctype.h>

#if !defined(_WIN32) && !defined(WIN32) && !defined(__MACOS__)
# include <signal.h>
# include <pwd.h>
# include <unistd.h>
# include <sys/types.h>
#endif

#ifdef __MACOS__
# include <console.h>
# include <signal.h>
# include <unistd.h>
# include <extras.h>
# include <Files.h>
# include <Folders.h>
#endif

#if defined(HAVE_READLINE) && HAVE_READLINE==1
# include <readline/readline.h>
# include <readline/history.h>
#else
# define readline(p) local_getline(p,stdin)
# define add_history(X)
# define read_history(X)
# define write_history(X)
# define stifle_history(X)
#endif

/* Make sure isatty() has a prototype.
*/
extern int isatty();

/*
** The following is the open SQLite database.  We make a pointer
** to this database a static variable so that it can be accessed
** by the SIGINT handler to interrupt database processing.
*/
static sqlite *db = 0;

/*
** True if an interrupt (Control-C) has been received.
*/
static int seenInterrupt = 0;

/*
** This is the name of our program. It is set in main(), used
** in a number of other places, mostly for error messages.
*/
static char *Argv0;

/*
** Prompt strings. Initialized in main. Settable with
**   .prompt main continue
*/
static char mainPrompt[20];     /* First line prompt. default: "sqlite> "*/
static char continuePrompt[20]; /* Continuation prompt. default: "   ...> " */


/*
** Determines if a string is a number of not.
*/
extern int sqliteIsNumber(const char*);

/*
** This routine reads a line of text from standard input, stores
** the text in memory obtained from malloc() and returns a pointer
** to the text.  NULL is returned at end of file, or if malloc()
** fails.
**
** The interface is like "readline" but no command-line editing
** is done.
*/
static char *local_getline(char *zPrompt, FILE *in){
  char *zLine;
  int nLine;
  int n;
  int eol;

  if( zPrompt && *zPrompt ){
    printf("%s",zPrompt);
    fflush(stdout);
  }
  nLine = 100;
  zLine = malloc( nLine );
  if( zLine==0 ) return 0;
  n = 0;
  eol = 0;
  while( !eol ){
    if( n+100>nLine ){
      nLine = nLine*2 + 100;
      zLine = realloc(zLine, nLine);
      if( zLine==0 ) return 0;
    }
    if( fgets(&zLine[n], nLine - n, in)==0 ){
      if( n==0 ){
        free(zLine);
        return 0;
      }
      zLine[n] = 0;
      eol = 1;
      break;
    }
    while( zLine[n] ){ n++; }
    if( n>0 && zLine[n-1]=='\n' ){
      n--;
      zLine[n] = 0;
      eol = 1;
    }
  }
  zLine = realloc( zLine, n+1 );
  return zLine;
}

/*
** Retrieve a single line of input text.  "isatty" is true if text
** is coming from a terminal.  In that case, we issue a prompt and
** attempt to use "readline" for command-line editing.  If "isatty"
** is false, use "local_getline" instead of "readline" and issue no prompt.
**
** zPrior is a string of prior text retrieved.  If not the empty
** string, then issue a continuation prompt.
*/
static char *one_input_line(const char *zPrior, FILE *in){
  char *zPrompt;
  char *zResult;
  if( in!=0 ){
    return local_getline(0, in);
  }
  if( zPrior && zPrior[0] ){
    zPrompt = continuePrompt;
  }else{
    zPrompt = mainPrompt;
  }
  zResult = readline(zPrompt);
  if( zResult ) add_history(zResult);
  return zResult;
}

struct previous_mode_data {
  int valid;        /* Is there legit data in here? */
  int mode;
  int showHeader;
  int colWidth[100];
};
/*
** An pointer to an instance of this structure is passed from
** the main program to the callback.  This is used to communicate
** state and mode information.
*/
struct callback_data {
  sqlite *db;            /* The database */
  int echoOn;            /* True to echo input commands */
  int cnt;               /* Number of records displayed so far */
  FILE *out;             /* Write results here */
  int mode;              /* An output mode setting */
  int showHeader;        /* True to show column names in List or Column mode */
  char *zDestTable;      /* Name of destination table when MODE_Insert */
  char separator[20];    /* Separator character for MODE_List */
  int colWidth[100];     /* Requested width of each column when in column mode*/
  int actualWidth[100];  /* Actual width of each column */
  char nullvalue[20];    /* The text to print when a NULL comes back from
                         ** the database */
  struct previous_mode_data explainPrev;
                         /* Holds the mode information just before
                         ** .explain ON */
  char outfile[FILENAME_MAX]; /* Filename for *out */
  const char *zDbFilename;    /* name of the database file */
};

/*
** These are the allowed modes.
*/
#define MODE_Line     0  /* One column per line.  Blank line between records */
#define MODE_Column   1  /* One record per line in neat columns */
#define MODE_List     2  /* One record per line with a separator */
#define MODE_Semi     3  /* Same as MODE_List but append ";" to each line */
#define MODE_Html     4  /* Generate an XHTML table */
#define MODE_Insert   5  /* Generate SQL "insert" statements */
#define MODE_NUM_OF   6  /* The number of modes (not a mode itself) */

char *modeDescr[MODE_NUM_OF] = {
  "line",
  "column",
  "list",
  "semi",
  "html",
  "insert"
};

/*
** Number of elements in an array
*/
#define ArraySize(X)  (sizeof(X)/sizeof(X[0]))

/*
** Output the given string as a quoted string using SQL quoting conventions.
*/
static void output_quoted_string(FILE *out, const char *z){
  int i;
  int nSingle = 0;
  for(i=0; z[i]; i++){
    if( z[i]=='\'' ) nSingle++;
  }
  if( nSingle==0 ){
    fprintf(out,"'%s'",z);
  }else{
    fprintf(out,"'");
    while( *z ){
      for(i=0; z[i] && z[i]!='\''; i++){}
      if( i==0 ){
        fprintf(out,"''");
        z++;
      }else if( z[i]=='\'' ){
        fprintf(out,"%.*s''",i,z);
        z += i+1;
      }else{
        fprintf(out,"%s",z);
        break;
      }
    }
    fprintf(out,"'");
  }
}

/*
** Output the given string with characters that are special to
** HTML escaped.
*/
static void output_html_string(FILE *out, const char *z){
  int i;
  while( *z ){
    for(i=0; z[i] && z[i]!='<' && z[i]!='&'; i++){}
    if( i>0 ){
      fprintf(out,"%.*s",i,z);
    }
    if( z[i]=='<' ){
      fprintf(out,"&lt;");
    }else if( z[i]=='&' ){
      fprintf(out,"&amp;");
    }else{
      break;
    }
    z += i + 1;
  }
}

/*
** This routine runs when the user presses Ctrl-C
*/
static void interrupt_handler(int NotUsed){
  seenInterrupt = 1;
  if( db ) sqlite_interrupt(db);
}

/*
** This is the callback routine that the SQLite library
** invokes for each row of a query result.
*/
static int callback(void *pArg, int nArg, char **azArg, char **azCol){
  int i;
  struct callback_data *p = (struct callback_data*)pArg;
  switch( p->mode ){
    case MODE_Line: {
      int w = 5;
      if( azArg==0 ) break;
      for(i=0; i<nArg; i++){
        int len = strlen(azCol[i]);
        if( len>w ) w = len;
      }
      if( p->cnt++>0 ) fprintf(p->out,"\n");
      for(i=0; i<nArg; i++){
        fprintf(p->out,"%*s = %s\n", w, azCol[i], 
                azArg[i] ? azArg[i] : p->nullvalue);
      }
      break;
    }
    case MODE_Column: {
      if( p->cnt++==0 ){
        for(i=0; i<nArg; i++){
          int w, n;
          if( i<ArraySize(p->colWidth) ){
             w = p->colWidth[i];
          }else{
             w = 0;
          }
          if( w<=0 ){
            w = strlen(azCol[i] ? azCol[i] : "");
            if( w<10 ) w = 10;
            n = strlen(azArg && azArg[i] ? azArg[i] : p->nullvalue);
            if( w<n ) w = n;
          }
          if( i<ArraySize(p->actualWidth) ){
            p->actualWidth[i] = w;
          }
          if( p->showHeader ){
            fprintf(p->out,"%-*.*s%s",w,w,azCol[i], i==nArg-1 ? "\n": "  ");
          }
        }
        if( p->showHeader ){
          for(i=0; i<nArg; i++){
            int w;
            if( i<ArraySize(p->actualWidth) ){
               w = p->actualWidth[i];
            }else{
               w = 10;
            }
            fprintf(p->out,"%-*.*s%s",w,w,"-----------------------------------"
                   "----------------------------------------------------------",
                    i==nArg-1 ? "\n": "  ");
          }
        }
      }
      if( azArg==0 ) break;
      for(i=0; i<nArg; i++){
        int w;
        if( i<ArraySize(p->actualWidth) ){
           w = p->actualWidth[i];
        }else{
           w = 10;
        }
        fprintf(p->out,"%-*.*s%s",w,w,
            azArg[i] ? azArg[i] : p->nullvalue, i==nArg-1 ? "\n": "  ");
      }
      break;
    }
    case MODE_Semi:
    case MODE_List: {
      if( p->cnt++==0 && p->showHeader ){
        for(i=0; i<nArg; i++){
          fprintf(p->out,"%s%s",azCol[i], i==nArg-1 ? "\n" : p->separator);
        }
      }
      if( azArg==0 ) break;
      for(i=0; i<nArg; i++){
        char *z = azArg[i];
        if( z==0 ) z = p->nullvalue;
        fprintf(p->out, "%s", z);
        if( i<nArg-1 ){
          fprintf(p->out, "%s", p->separator);
        }else if( p->mode==MODE_Semi ){
          fprintf(p->out, ";\n");
        }else{
          fprintf(p->out, "\n");
        }
      }
      break;
    }
    case MODE_Html: {
      if( p->cnt++==0 && p->showHeader ){
        fprintf(p->out,"<TR>");
        for(i=0; i<nArg; i++){
          fprintf(p->out,"<TH>%s</TH>",azCol[i]);
        }
        fprintf(p->out,"</TR>\n");
      }
      if( azArg==0 ) break;
      fprintf(p->out,"<TR>");
      for(i=0; i<nArg; i++){
        fprintf(p->out,"<TD>");
        output_html_string(p->out, azArg[i] ? azArg[i] : p->nullvalue);
        fprintf(p->out,"</TD>\n");
      }
      fprintf(p->out,"</TR>\n");
      break;
    }
    case MODE_Insert: {
      if( azArg==0 ) break;
      fprintf(p->out,"INSERT INTO %s VALUES(",p->zDestTable);
      for(i=0; i<nArg; i++){
        char *zSep = i>0 ? ",": "";
        if( azArg[i]==0 ){
          fprintf(p->out,"%sNULL",zSep);
        }else if( sqliteIsNumber(azArg[i]) ){
          fprintf(p->out,"%s%s",zSep, azArg[i]);
        }else{
          if( zSep[0] ) fprintf(p->out,"%s",zSep);
          output_quoted_string(p->out, azArg[i]);
        }
      }
      fprintf(p->out,");\n");
      break;
    }
  }
  return 0;
}

/*
** Set the destination table field of the callback_data structure to
** the name of the table given.  Escape any quote characters in the
** table name.
*/
static void set_table_name(struct callback_data *p, const char *zName){
  int i, n;
  int needQuote;
  char *z;

  if( p->zDestTable ){
    free(p->zDestTable);
    p->zDestTable = 0;
  }
  if( zName==0 ) return;
  needQuote = !isalpha(*zName) && *zName!='_';
  for(i=n=0; zName[i]; i++, n++){
    if( !isalnum(zName[i]) && zName[i]!='_' ){
      needQuote = 1;
      if( zName[i]=='\'' ) n++;
    }
  }
  if( needQuote ) n += 2;
  z = p->zDestTable = malloc( n+1 );
  if( z==0 ){
    fprintf(stderr,"Out of memory!\n");
    exit(1);
  }
  n = 0;
  if( needQuote ) z[n++] = '\'';
  for(i=0; zName[i]; i++){
    z[n++] = zName[i];
    if( zName[i]=='\'' ) z[n++] = '\'';
  }
  if( needQuote ) z[n++] = '\'';
  z[n] = 0;
}

/*
** This is a different callback routine used for dumping the database.
** Each row received by this callback consists of a table name,