runtime/io.c

   1 /* -*- linux-c -*-
   2  * I/O for printing warnings, errors and debug messages
   3  * Copyright (C) 2005, 2006, 2007 Red Hat Inc.
   4  *
   5  * This file is part of systemtap, and is free software.  You can
   6  * redistribute it and/or modify it under the terms of the GNU General
   7  * Public License (GPL); either version 2, or (at your option) any
   8  * later version.
   9  */
  10
  11 #ifndef _IO_C_
  12 #define _IO_C_
  13
  14 #include "transport/transport.c"
  15
  16 void _stp_print_flush (void);
  17 void _stp_string_cat_cstr (String str1, const char *str2);
  18
  19 /** @file io.c
  20  * @brief I/O for printing warnings, errors and debug messages.
  21  */
  22 /** @addtogroup io I/O
  23  * @{
  24  */
  25
  26 #define WARN_STRING "WARNING: "
  27 #define ERR_STRING "ERROR: "
  28 enum code { INFO=0, WARN, ERROR, DBUG };
  29
  30 /** private buffer for _stp_log() */
  31 #define STP_LOG_BUF_LEN 256
  32
  33 typedef char _stp_lbuf[STP_LOG_BUF_LEN];
  34 void *Stp_lbuf = NULL;
  35
  36 static void _stp_vlog (enum code type, const char *func, int line, const char *fmt, va_list args)
  37 {
  38         int num;
  39         char *buf = per_cpu_ptr(Stp_lbuf, smp_processor_id());
  40         int start = 0;
  41
  42         if (type == DBUG) {
  43                 start = _stp_snprintf(buf, STP_LOG_BUF_LEN, "\033[36m%s:%d:\033[0m ", func, line);
  44         } else if (type == WARN) {
  45                 strcpy (buf, WARN_STRING);
  46                 start = sizeof(WARN_STRING) - 1;
  47         } else if (type == ERROR) {
  48                 strcpy (buf, ERR_STRING);
  49                 start = sizeof(ERR_STRING) - 1;
  50         }
  51
  52         num = _stp_vscnprintf (buf + start, STP_LOG_BUF_LEN - start - 1, fmt, args);
  53         if (num + start) {
  54                 if (buf[num + start - 1] != '\n') {
  55                         buf[num + start] = '\n';
  56                         num++;
  57                         buf[num + start] = '\0';
  58                 }
  59
  60                 if (type != DBUG)
  61                         _stp_write(STP_OOB_DATA, buf, start + num + 1);
  62                 else {
  63                         _stp_string_cat_cstr(_stp_stdout,buf);
  64                         _stp_print_flush();
  65                 }
  66         }
  67 }
  68
  69 /** Logs Data.
  70  * This function sends the message immediately to staprun. It
  71  * will also be sent over the bulk transport (relayfs) if it is
  72  * being used. If the last character is not a newline, then one
  73  * is added. This function is not as efficient as _stp_printf()
  74  * and should only be used for urgent messages. You probably want
  75  * dbug(), or _stp_warn().
  76  * @param fmt A variable number of args.
  77  * @todo Evaluate if this function is necessary.
  78  */
  79 void _stp_log (const char *fmt, ...)
  80 {
  81         va_list args;
  82         va_start(args, fmt);
  83         _stp_vlog (INFO, NULL, 0, fmt, args);
  84         va_end(args);
  85 }
  86
  87 /** Prints warning.
  88  * This function sends a warning message immediately to staprun. It
  89  * will also be sent over the bulk transport (relayfs) if it is
  90  * being used. If the last character is not a newline, then one
  91  * is added.
  92  * @param fmt A variable number of args.
  93  */
  94 void _stp_warn (const char *fmt, ...)
  95 {
  96         va_list args;
  97         va_start(args, fmt);
  98         _stp_vlog (WARN, NULL, 0, fmt, args);
  99         va_end(args);
 100 }
 101
 102 /** Exits and unloads the module.
 103  * This function sends a signal to staprun to tell it to
 104  * unload the module and exit. The module will not be
 105  * unloaded until after the current probe returns.
 106  * @note Be careful to not treat this like the Linux exit()
 107  * call. You should probably call return immediately after
 108  * calling _stp_exit().
 109  */
 110 void _stp_exit (void)
 111 {
 112         _stp_exit_flag = 1;
 113 }
 114
 115 /** Prints error message and exits.
 116  * This function sends an error message immediately to staprun. It
 117  * will also be sent over the bulk transport (relayfs) if it is
 118  * being used. If the last character is not a newline, then one
 119  * is added.
 120  *
 121  * After the error message is displayed, the module will be unloaded.
 122  * @param fmt A variable number of args.
 123  * @sa _stp_exit().
 124  */
 125 void _stp_error (const char *fmt, ...)
 126 {
 127         va_list args;
 128         va_start(args, fmt);
 129         _stp_vlog (ERROR, NULL, 0, fmt, args);
 130         va_end(args);
 131         _stp_exit();
 132 }
 133
 134
 135 /** Prints error message.
 136  * This function sends an error message immediately to staprun. It
 137  * will also be sent over the bulk transport (relayfs) if it is
 138  * being used. If the last character is not a newline, then one
 139  * is added.
 140  *
 141  * @param fmt A variable number of args.
 142  * @sa _stp_error
 143  */
 144 void _stp_softerror (const char *fmt, ...)
 145 {
 146         va_list args;
 147         va_start(args, fmt);
 148         _stp_vlog (ERROR, NULL, 0, fmt, args);
 149         va_end(args);
 150 }
 151
 152
 153 static void _stp_dbug (const char *func, int line, const char *fmt, ...)
 154 {
 155         va_list args;
 156         va_start(args, fmt);
 157         _stp_vlog (DBUG, func, line, fmt, args);
 158         va_end(args);
 159 }
 160
 161 /** @} */
 162 #endif /* _IO_C_ */