gitweb.ps.run Git - ps-cgit/blob - filter.c

   1 /* filter.c: filter framework functions
   2  *
   3  * Copyright (C) 2006-2014 cgit Development Team <cgit@lists.zx2c4.com>
   4  *
   5  * Licensed under GNU General Public License v2
   6  *   (see COPYING for full license text)
   7  */
   8
   9 #include "cgit.h"
  10 #include <sys/types.h>
  11 #include <sys/wait.h>
  12 #include <unistd.h>
  13 #include <string.h>
  14 #include <stdlib.h>
  15
  16 static inline void reap_filter(struct cgit_filter *filter)
  17 {
  18         if (filter && filter->cleanup)
  19                 filter->cleanup(filter);
  20 }
  21
  22 void cgit_cleanup_filters(void)
  23 {
  24         int i;
  25         reap_filter(ctx.cfg.about_filter);
  26         reap_filter(ctx.cfg.commit_filter);
  27         reap_filter(ctx.cfg.source_filter);
  28         for (i = 0; i < cgit_repolist.count; ++i) {
  29                 reap_filter(cgit_repolist.repos[i].about_filter);
  30                 reap_filter(cgit_repolist.repos[i].commit_filter);
  31                 reap_filter(cgit_repolist.repos[i].source_filter);
  32         }
  33 }
  34
  35 static int open_exec_filter(struct cgit_filter *base, va_list ap)
  36 {
  37         struct cgit_exec_filter *filter = (struct cgit_exec_filter *) base;
  38         int i;
  39
  40         for (i = 0; i < filter->extra_args; i++)
  41                 filter->argv[i+1] = va_arg(ap, char *);
  42
  43         filter->old_stdout = chk_positive(dup(STDOUT_FILENO),
  44                 "Unable to duplicate STDOUT");
  45         chk_zero(pipe(filter->pipe_fh), "Unable to create pipe to subprocess");
  46         filter->pid = chk_non_negative(fork(), "Unable to create subprocess");
  47         if (filter->pid == 0) {
  48                 close(filter->pipe_fh[1]);
  49                 chk_non_negative(dup2(filter->pipe_fh[0], STDIN_FILENO),
  50                         "Unable to use pipe as STDIN");
  51                 execvp(filter->cmd, filter->argv);
  52                 die_errno("Unable to exec subprocess %s", filter->cmd);
  53         }
  54         close(filter->pipe_fh[0]);
  55         chk_non_negative(dup2(filter->pipe_fh[1], STDOUT_FILENO),
  56                 "Unable to use pipe as STDOUT");
  57         close(filter->pipe_fh[1]);
  58         return 0;
  59 }
  60
  61 static int close_exec_filter(struct cgit_filter *base)
  62 {
  63         struct cgit_exec_filter *filter = (struct cgit_exec_filter *) base;
  64         int i, exit_status;
  65
  66         chk_non_negative(dup2(filter->old_stdout, STDOUT_FILENO),
  67                 "Unable to restore STDOUT");
  68         close(filter->old_stdout);
  69         if (filter->pid < 0)
  70                 goto done;
  71         waitpid(filter->pid, &exit_status, 0);
  72         if (WIFEXITED(exit_status) && !WEXITSTATUS(exit_status))
  73                 goto done;
  74         die("Subprocess %s exited abnormally", filter->cmd);
  75
  76 done:
  77         for (i = 0; i < filter->extra_args; i++)
  78                 filter->argv[i+1] = NULL;
  79         return 0;
  80
  81 }
  82
  83 static void fprintf_exec_filter(struct cgit_filter *base, FILE *f, const char *prefix)
  84 {
  85         struct cgit_exec_filter *filter = (struct cgit_exec_filter *) base;
  86         fprintf(f, "%sexec:%s\n", prefix, filter->cmd);
  87 }
  88
  89 static void cleanup_exec_filter(struct cgit_filter *base)
  90 {
  91         struct cgit_exec_filter *filter = (struct cgit_exec_filter *) base;
  92         if (filter->argv) {
  93                 free(filter->argv);
  94                 filter->argv = NULL;
  95         }
  96         if (filter->cmd) {
  97                 free(filter->cmd);
  98                 filter->cmd = NULL;
  99         }
 100 }
 101
 102 static struct cgit_filter *new_exec_filter(const char *cmd, filter_type filtertype)
 103 {
 104         struct cgit_exec_filter *f;
 105         int args_size = 0;
 106
 107         f = xmalloc(sizeof(*f));
 108         /* We leave argv for now and assign it below. */
 109         cgit_exec_filter_init(f, xstrdup(cmd), NULL);
 110
 111         switch (filtertype) {
 112                 case SOURCE:
 113                 case ABOUT:
 114                         f->extra_args = 1;
 115                         break;
 116
 117                 case COMMIT:
 118                 default:
 119                         f->extra_args = 0;
 120                         break;
 121         }
 122
 123         args_size = (2 + f->extra_args) * sizeof(char *);
 124         f->argv = xmalloc(args_size);
 125         memset(f->argv, 0, args_size);
 126         f->argv[0] = f->cmd;
 127         return &f->base;
 128 }
 129
 130 void cgit_exec_filter_init(struct cgit_exec_filter *filter, char *cmd, char **argv)
 131 {
 132         memset(filter, 0, sizeof(*filter));
 133         filter->base.open = open_exec_filter;
 134         filter->base.close = close_exec_filter;
 135         filter->base.fprintf = fprintf_exec_filter;
 136         filter->base.cleanup = cleanup_exec_filter;
 137         filter->cmd = cmd;
 138         filter->argv = argv;
 139 }
 140
 141 int cgit_open_filter(struct cgit_filter *filter, ...)
 142 {
 143         int result;
 144         va_list ap;
 145         va_start(ap, filter);
 146         result = filter->open(filter, ap);
 147         va_end(ap);
 148         return result;
 149 }
 150
 151 int cgit_close_filter(struct cgit_filter *filter)
 152 {
 153         return filter->close(filter);
 154 }
 155
 156 void cgit_fprintf_filter(struct cgit_filter *filter, FILE *f, const char *prefix)
 157 {
 158         filter->fprintf(filter, f, prefix);
 159 }
 160
 161
 162
 163 static const struct {
 164         const char *prefix;
 165         struct cgit_filter *(*ctor)(const char *cmd, filter_type filtertype);
 166 } filter_specs[] = {
 167         { "exec", new_exec_filter },
 168 };
 169
 170 struct cgit_filter *cgit_new_filter(const char *cmd, filter_type filtertype)
 171 {
 172         char *colon;
 173         int i;
 174         size_t len;
 175         if (!cmd || !cmd[0])
 176                 return NULL;
 177
 178         colon = strchr(cmd, ':');
 179         len = colon - cmd;
 180         /*
 181          * In case we're running on Windows, don't allow a single letter before
 182          * the colon.
 183          */
 184         if (len == 1)
 185                 colon = NULL;
 186
 187         /* If no prefix is given, exec filter is the default. */
 188         if (!colon)
 189                 return new_exec_filter(cmd, filtertype);
 190
 191         for (i = 0; i < ARRAY_SIZE(filter_specs); i++) {
 192                 if (len == strlen(filter_specs[i].prefix) &&
 193                     !strncmp(filter_specs[i].prefix, cmd, len))
 194                         return filter_specs[i].ctor(colon + 1, filtertype);
 195         }
 196
 197         die("Invalid filter type: %.*s", (int) len, cmd);
 198 }
 199