文本文件有关操作

/* 
通用C语言函数：文本文件有关操作，.CFG/.INI类配置文件读写。我们知道WINDOWS下的软件可以使用.INI文件 
处理程序配置，那么在DOS、UNIX、AS/400上又如何才能读写.CFG/.INI类配置文件? 你可以使用本程序的有关函 
数很方便地实现。注：AS/400上输入和显示[]有些问题，所以用{}代替来将section名括起。 

   GCFTXTF.C -- General C functions for Text File Read/Write 
   M.L.Y  2000.1.1 

   MODIFIED   (YYYY.MM.DD) 
    M.L.Y      2000.01.01 -  Creation 
*/ 

#if __OS400__                         /* AS/400 */ 
  #include "GCFTXTFH" 
#else 
# include "GCFTXTF.H" 
#endif 

struct txt_line_flds txt_line_fld[MAX_TXT_LINE_FLD]; 
char CFG_ssl = '[', CFG_ssr = ']';  /* .CFG/.INI file section symbol */ 
int  CFG_section_line_no, CFG_key_line_no, CFG_key_lines; 

/* ------------------------------------------------------------------------- */ 
int  fgetline(FILE *fp, USGC *buffer, int maxlen) 
/* 
   Read 1 line text into *buffer from file *fp, return length actually read. 
   maxlen --- max. length of *buffer 
   CR or LF is not put into *buffer 
   FF(0x0C) is put into *buffer and then return 
   Ctrl-Z(0x1A) is put into *buffer and then return 
   If EOF was detected then return -1 
   If an error occurred then return -2 
   M.L.Y  1995.06.09, 07.31, 1998.9.9 
*/ 
{ 
#if __OS400__                         /* AS/400 */ 
  int  i; 

  memset(buffer, 0x00, maxlen); 
  if(fgets(buffer, maxlen, fp) == NULL) 
  { 
    i = strlen(buffer); 
    if(feof(fp) != 0) 
    { 
      if(i == 0) return -1;                 /* EOF */ 
    } 
    else return -2;                         /* error */ 
  } 
  i = strlen(buffer); 
  if(i > 0 && buffer[i-1] == '\n') 
    buffer[--i] = '\0'; 
  return i; 
#else 
  int  i, j; 
  USGC ch1; 

  for(i = 0, j = 0; i < maxlen; j++) 
  { 
    if(fread(&ch1, sizeof(USGC), 1, fp) != 1) 
    { 
      if(feof(fp) != 0) 
      { 
        if(j == 0) return -1;               /* EOF */ 
        else break; 
      } 
      if(ferror(fp) != 0) return -2;        /* error */ 
      return -2; 
    } 
    else 
    { 
      if(ch1 == '\n' || ch1 == 0x00) break; /* end of line */ 
      if(ch1 == '\f' || ch1 == 0x1A)        /* '\f': Form Feed */ 
      { 
        buffer[i++] = ch1; 
        break; 
      } 
      if(ch1 != '\r') buffer[i++] = ch1;    /* ignore CR */ 
    } 
  } 
  buffer[i] = '\0'; 
  return i; 
#endif 
} 

/* ------------------------------------------------------------------------- */ 
int  copy_txt_file(void *source_file, void *dest_file) 
/* 
   Copy source_file to dest_file 
   Return code: 
      0 -- Ok 
     <0 -- Error 
   M.L.Y  1996.7, 2000.11 
*/ 
{ 
  FILE *fp1, *fp2; 
  USGC buf[1024+1]; 
  int  rc; 

  if((fp1 = fopen((char *)source_file, "r")) == NULL) 
    return COPYF_ERR_OPEN_FILE; 
  rc = COPYF_ERR_CREATE_FILE; 
#if __OS400__                         /* AS/400 */ 
  if((fp2 = fopen((char *)dest_file, "w, lrecl=92, ccsid=935")) == NULL) 
    goto copy_end; 
#else 
  if((fp2 = fopen((char *)dest_file, "w")) == NULL) goto copy_end; 
#endif 
  while(1) 
  { 
    rc = COPYF_ERR_READ_FILE; 
    memset(buf, 0x00, 1024+1); 
    if(fgets((char *)buf, 1024, fp1) == NULL) 
    { 
      if(mstrlen(buf) == 0) 
      { 
        if(ferror(fp1) != 0) goto copy_end; 
        break;                                   /* EOF */ 
      } 
    } 
    rc = COPYF_ERR_WRITE_FILE; 
    if(fputs((char *)buf, fp2) == EOF) goto copy_end; 
  } 
  rc = COPYF_OK; 
copy_end: 
  if(fp2 != NULL) fclose(fp2); 
  if(fp1 != NULL) fclose(fp1); 
  return rc; 
} 

/* ------------------------------------------------------------------------- */ 
int  split_txt_line_fld(char *txt_line, char *sep_chars) 
/* 
   Split a text line fields info to struct txt_line_fld 
   Return fld number 
   e.g.: fld1 = fld2, fld3, "fld4", 'fld5' 
         key = value 

   M.L.Y  2000.8.2 
*/ 
{ 
  int  i, j, k, n, stat = 0, quote_stat = 0; 
  char quote; 

  n = strlen(txt_line); 
  for(i = 0, j = 0, k = 0; i <= n; i++) 
  { 
    if(i >= n || 
       (strchr(sep_chars, txt_line[i]) != NULL && quote_stat == 0)) 
    { 
      if(stat == 0) continue; 
      stat = 0;                         /* is separate char */ 
      txt_line_fld[k].fldsp = j; 
      txt_line_fld[k].fldlen = i - j; 
      k++; 
    } 
    else 
    { 
      if(txt_line[i] == '\'' || txt_line[i] == '\"') 
      { 
        if(quote_stat == 0) 
        { 
          quote = txt_line[i];          /* " or ' */ 
          quote_stat = 1;               /* enter " " or ' ' */ 
        } 
        else 
        { 
          if(txt_line[i] == quote) 
            quote_stat = 0;             /* withdraw from " " or ' ' */ 
        } 
      } 
      if(stat == 1) continue; 
      stat = 1;                         /* is normal char */ 
      j = i;                            /* fld start pointer */ 
    } 
  } 
  return k;                             /* fld number */ 
} 

/* ------------------------------------------------------------------------- */ 
char *get_txt_line_fld(char *txt_line, int fldno, char *buf) 
/* 
   After split a text line fields info to struct txt_line_fld, 
   get the fldno fld to buf 
   Return buf 

   M.L.Y  2000.8.2 
*/ 
{ 
  memmove(buf, txt_line + txt_line_fld[fldno].fldsp, 
          txt_line_fld[fldno].fldlen); 
  buf[txt_line_fld[fldno].fldlen] = '\0'; 
  return buf; 
} 

/* ------------------------------------------------------------------------- */ 
int  split_key_val(USGC *buf, USGC **key, USGC **val) 
/* 
   Split key=val pair: 
   xxx    =   yyyyyyyy 
   |      |   | 
   k1     k2  i 
   return: 
     1 --- ok 
     0 --- blank line 
    -1 --- no key, "= val" 
    -2 --- only key, no '=' 

   M.L.Y  2000.8, 2000.11 
*/ 
{ 
  int  i, k1, k2, n; 

  if((n = strlen((char *)buf)) < 1) return 0; 
  for(i = 0; i < n; i++) 
    if(buf[i] != ' ' && buf[i] != '\t') break; 
  if(i >= n) return 0; 
  if(buf[i] == '=') return -1; 
  k1 = i; 
  for(i++; i < n; i++) 
    if(buf[i] == '=') break; 
  if(i >= n) return -2; 
  k2 = i; 
  for(i++; i < n; i++) 
    if(buf[i] != ' ' && buf[i] != '\t') break; 
  buf[k2] = '\0'; 
  *key = buf + k1; 
  *val = buf + i; 
  return 1; 
} 

/* ------------------------------------------------------------------------- */ 
int  CFG_get_key(void *CFG_file, void *section, void *key, void *buf) 
/* 
   Note: 
    section --- not include [] or {} 
    key     --- may include blank space 
    blank line or begin with ';' for remarks 
    line end with '+' for line to be continued 

   Return: 
     0 --- ok 
    <0 --- error 
*/ 
{ 
  FILE *fp; 
  USGC buf1[MAX_CFG_BUF + 1], buf2[MAX_CFG_BUF + 1]; 
  USGC *key_ptr, *val_ptr; 
  int  line_no, n, rc; 

  line_no = 0; 
  CFG_section_line_no = 0; 
  CFG_key_line_no = 0; 
  CFG_key_lines = 0; 
#if __OS400__                         /* AS/400 */ 
  if((fp = fopen((char *)CFG_file, "r")) == NULL) return CFG_ERR_OPEN_FILE; 
#else 
  if((fp = fopen((char *)CFG_file, "rb")) == NULL) return CFG_ERR_OPEN_FILE; 
#endif 
  while(1)                                       /* seek section */ 
  { 
    rc = CFG_ERR_READ_FILE; 
    n = fgetline(fp, buf1, MAX_CFG_BUF); 
    if(n < -1) goto r_cfg_end; 
    rc = CFG_SECTION_NOT_FOUND; 
    if(n < 0) goto r_cfg_end;                    /* EOF, not found */ 
    line_no++; 
    n = mstrlen(ltrimstr(rtrimstr(buf1))); 
    if(n == 0 || buf1[0] == ';') continue;       /* blank/remarks line */ 
    rc = CFG_ERR_FILE_FORMAT; 
    if(n > 2 && ((buf1[0] == '[' && buf1[n-1] != ']') || 
                 (buf1[0] == '{' && buf1[n-1] != '}'))) 
      goto r_cfg_end; 
    if(buf1[0] == '[' || buf1[0] == '{') 
    { 
      buf1[n-1] = 0x00; 
      if(mstrcmp(buf1+1, section) == 0) 
        break;                                   /* section found */ 
    } 
  } 
  CFG_section_line_no = line_no; 
  while(1)                                       /* seek key */ 
  { 
    rc = CFG_ERR_READ_FILE; 
    n = fgetline(fp, buf1, MAX_CFG_BUF); 
    if(n < -1) goto r_cfg_end; 
    rc = CFG_KEY_NOT_FOUND; 
    if(n < 0) goto r_cfg_end;                    /* EOF, key not found */ 
    line_no++; 
    CFG_key_line_no = line_no; 
    CFG_key_lines = 1; 
    n = mstrlen(ltrimstr(rtrimstr(buf1))); 
    if(n == 0 || buf1[0] == ';') continue;       /* blank/remarks line */ 
    rc = CFG_KEY_NOT_FOUND; 
    if(buf1[0] == '[' || buf1[0] == '{') goto r_cfg_end; 
    if(buf1[n-1] == '+')                         /* to be continued */ 
    { 
      buf1[n-1] = 0x00; 
      while(1) 
      { 
        rc = CFG_ERR_READ_FILE; 
        n = fgetline(fp, buf2, MAX_CFG_BUF); 
        if(n < -1) goto r_cfg_end; 
        if(n < 0) break;                         /* EOF */ 
        line_no++; 
        CFG_key_lines++; 
        n = mstrlen(rtrimstr(buf2)); 
        rc = CFG_ERR_EXCEED_BUF_SIZE; 
        if(n > 0 && buf2[n-1] == '+')            /* to be continued */ 
        { 
          buf2[n-1] = 0x00; 
          if(mstrlen(buf1) + mstrlen(buf2) > MAX_CFG_BUF) 
            goto r_cfg_end; 
          mstrcat(buf1, buf2); 
          continue; 
        } 
        if(mstrlen(buf1) + mstrlen(buf2) > MAX_CFG_BUF) 
          goto r_cfg_end; 
        mstrcat(buf1, buf2); 
        break; 
      } 
    } 
    rc = CFG_ERR_FILE_FORMAT; 
    if(split_key_val(buf1, &key_ptr, &val_ptr) != 1) 
      goto r_cfg_end; 
    ltrimstr(rtrimstr(key_ptr)); 
    if(mstrcmp(key_ptr, key) != 0) 
      continue;                                  /* not same key */ 
    mstrcpy(buf, val_ptr); 
    break;