Branch for wmfs2

src/util.c

@@ -0,0 +1,128 @@
+/*
+ *  wmfs2 by Martin Duquesnoy <xorg62@gmail.com> { for(i = 2011; i < 2111; ++i) ©(i); }
+ *  For license, see COPYING.
+ */
+
+#define _GNU_SOURCE /* vasprintf() */
+
+#include <stdint.h>
+#include <string.h>
+
+#include "util.h"
+
+/** malloc with error support and size_t overflow protection
+ * \param nmemb number of objects
+ * \param size size of single object
+ * \return non null void pointer
+ */
+void*
+xmalloc(size_t nmemb, size_t size)
+{
+     void *ret;
+
+     if(SIZE_MAX / nmemb < size)
+          err(EXIT_FAILURE, "xmalloc(%zu, %zu), "
+                    "size_t overflow detected", nmemb, size);
+
+     if((ret = malloc(nmemb * size)) == NULL)
+          err(EXIT_FAILURE, "malloc(%zu)", nmemb * size);
+
+     return ret;
+}
+
+/** calloc with error support
+ * \param nmemb Number of objects
+ * \param size size of single object
+ * \return non null void pointer
+*/
+void*
+xcalloc(size_t nmemb, size_t size)
+{
+     void *ret;
+
+     if((ret = calloc(nmemb, size)) == NULL)
+          err(EXIT_FAILURE, "calloc(%zu * %zu)", nmemb, size);
+
+     return ret;
+}
+
+/** asprintf wrapper
+ * \param strp target string
+ * \param fmt format
+ * \return non zero integer
+ */
+int
+xasprintf(char **strp, const char *fmt, ...)
+{
+     int ret;
+     va_list args;
+
+     va_start(args, fmt);
+     ret = vasprintf(strp, fmt, args);
+     va_end(args);
+
+     if (ret == -1)
+          err(EXIT_FAILURE, "asprintf(%s)", fmt);
+
+     return ret;
+}
+
+/** strdup with error support
+ * \param str char pointer
+ * \retun non null void pointer
+ */
+char *
+xstrdup(const char *str)
+{
+     char *ret;
+
+     if (str == NULL || (ret = strdup(str)) == NULL)
+          err(EXIT_FAILURE, "strdup(%s)", str);
+
+     return ret;
+}
+
+/** Execute a system command
+ * \param cmd Command
+ * \return child pid
+*/
+pid_t
+spawn(const char *format, ...)
+{
+     char *sh = NULL;
+     char cmd[512];
+     va_list ap;
+     pid_t pid;
+     size_t len;
+
+     va_start(ap, format);
+     len = vsnprintf(cmd, sizeof(cmd), format, ap);
+     va_end(ap);
+
+     if (len >= sizeof(cmd))
+     {
+          warnx("command too long (> 512 bytes)");
+          return -1;
+     }
+
+     if(!(sh = getenv("SHELL")))
+          sh = "/bin/sh";
+
+     if((pid = fork()) == 0)
+     {
+          setsid();
+          if (execl(sh, sh, "-c", cmd, (char*)NULL) == -1)
+               warn("execl(sh -c %s)", cmd);
+          exit(EXIT_FAILURE);
+     }
+     else if (pid == -1)
+          warn("fork");
+
+     return pid;
+}
+
+void
+uicb_spawn(Uicb cmd)
+{
+     spawn("%s", cmd);
+}