Andrew's git - gitweb.git/blob

   1/*
   2 * GIT - The information manager from hell
   3 *
   4 * Copyright (C) 2000-2002 Michael R. Elkins <me@mutt.org>
   5 * Copyright (C) 2002-2004 Oswald Buddenhagen <ossi@users.sf.net>
   6 * Copyright (C) 2004 Theodore Y. Ts'o <tytso@mit.edu>
   7 * Copyright (C) 2006 Mike McCormack
   8 * Copyright (C) 2006 Christian Couder
   9 *
  10 *  This program is free software; you can redistribute it and/or modify
  11 *  it under the terms of the GNU General Public License as published by
  12 *  the Free Software Foundation; either version 2 of the License, or
  13 *  (at your option) any later version.
  14 *
  15 *  This program is distributed in the hope that it will be useful,
  16 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 *  GNU General Public License for more details.
  19 *
  20 *  You should have received a copy of the GNU General Public License
  21 *  along with this program; if not, write to the Free Software
  22 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23 */
  24
  25#include "cache.h"
  26#include "quote.h"
  27
  28static void do_nothing(size_t unused)
  29{
  30}
  31
  32/* Get a trace file descriptor from GIT_TRACE env variable. */
  33static int get_trace_fd(int *need_close)
  34{
  35        char *trace = getenv("GIT_TRACE");
  36
  37        if (!trace || !strcmp(trace, "") ||
  38            !strcmp(trace, "0") || !strcasecmp(trace, "false"))
  39                return 0;
  40        if (!strcmp(trace, "1") || !strcasecmp(trace, "true"))
  41                return STDERR_FILENO;
  42        if (strlen(trace) == 1 && isdigit(*trace))
  43                return atoi(trace);
  44        if (is_absolute_path(trace)) {
  45                int fd = open(trace, O_WRONLY | O_APPEND | O_CREAT, 0666);
  46                if (fd == -1) {
  47                        fprintf(stderr,
  48                                "Could not open '%s' for tracing: %s\n"
  49                                "Defaulting to tracing on stderr...\n",
  50                                trace, strerror(errno));
  51                        return STDERR_FILENO;
  52                }
  53                *need_close = 1;
  54                return fd;
  55        }
  56
  57        fprintf(stderr, "What does '%s' for GIT_TRACE mean?\n", trace);
  58        fprintf(stderr, "If you want to trace into a file, "
  59                "then please set GIT_TRACE to an absolute pathname "
  60                "(starting with /).\n");
  61        fprintf(stderr, "Defaulting to tracing on stderr...\n");
  62
  63        return STDERR_FILENO;
  64}
  65
  66static const char err_msg[] = "Could not trace into fd given by "
  67        "GIT_TRACE environment variable";
  68
  69void trace_printf(const char *fmt, ...)
  70{
  71        struct strbuf buf;
  72        va_list ap;
  73        int fd, len, need_close = 0;
  74
  75        fd = get_trace_fd(&need_close);
  76        if (!fd)
  77                return;
  78
  79        set_try_to_free_routine(do_nothing);    /* is never reset */
  80        strbuf_init(&buf, 64);
  81        va_start(ap, fmt);
  82        len = vsnprintf(buf.buf, strbuf_avail(&buf), fmt, ap);
  83        va_end(ap);
  84        if (len >= strbuf_avail(&buf)) {
  85                strbuf_grow(&buf, len - strbuf_avail(&buf) + 128);
  86                va_start(ap, fmt);
  87                len = vsnprintf(buf.buf, strbuf_avail(&buf), fmt, ap);
  88                va_end(ap);
  89                if (len >= strbuf_avail(&buf))
  90                        die("broken vsnprintf");
  91        }
  92        strbuf_setlen(&buf, len);
  93
  94        write_or_whine_pipe(fd, buf.buf, buf.len, err_msg);
  95        strbuf_release(&buf);
  96
  97        if (need_close)
  98                close(fd);
  99}
 100
 101void trace_argv_printf(const char **argv, const char *fmt, ...)
 102{
 103        struct strbuf buf;
 104        va_list ap;
 105        int fd, len, need_close = 0;
 106
 107        fd = get_trace_fd(&need_close);
 108        if (!fd)
 109                return;
 110
 111        set_try_to_free_routine(do_nothing);    /* is never reset */
 112        strbuf_init(&buf, 64);
 113        va_start(ap, fmt);
 114        len = vsnprintf(buf.buf, strbuf_avail(&buf), fmt, ap);
 115        va_end(ap);
 116        if (len >= strbuf_avail(&buf)) {
 117                strbuf_grow(&buf, len - strbuf_avail(&buf) + 128);
 118                va_start(ap, fmt);
 119                len = vsnprintf(buf.buf, strbuf_avail(&buf), fmt, ap);
 120                va_end(ap);
 121                if (len >= strbuf_avail(&buf))
 122                        die("broken vsnprintf");
 123        }
 124        strbuf_setlen(&buf, len);
 125
 126        sq_quote_argv(&buf, argv, 0);
 127        strbuf_addch(&buf, '\n');
 128        write_or_whine_pipe(fd, buf.buf, buf.len, err_msg);
 129        strbuf_release(&buf);
 130
 131        if (need_close)
 132                close(fd);
 133}