diff options
Diffstat (limited to 'tools/gator/daemon/DynBuf.cpp')
-rw-r--r-- | tools/gator/daemon/DynBuf.cpp | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/tools/gator/daemon/DynBuf.cpp b/tools/gator/daemon/DynBuf.cpp new file mode 100644 index 000000000000..6f92b336ae19 --- /dev/null +++ b/tools/gator/daemon/DynBuf.cpp @@ -0,0 +1,139 @@ +/** + * Copyright (C) ARM Limited 2013-2014. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include "DynBuf.h" + +#include <errno.h> +#include <fcntl.h> +#include <stdarg.h> +#include <stdio.h> +#include <unistd.h> + +#include "Logging.h" + +// Pick an aggressive size as buffer is primarily used for disk IO +#define MIN_BUFFER_FREE (1 << 12) + +int DynBuf::resize(const size_t minCapacity) { + size_t scaledCapacity = 2 * capacity; + if (scaledCapacity < minCapacity) { + scaledCapacity = minCapacity; + } + if (scaledCapacity < 2 * MIN_BUFFER_FREE) { + scaledCapacity = 2 * MIN_BUFFER_FREE; + } + capacity = scaledCapacity; + + buf = static_cast<char *>(realloc(buf, capacity)); + if (buf == NULL) { + return -errno; + } + + return 0; +} + +bool DynBuf::read(const char *const path) { + int result = false; + + const int fd = open(path, O_RDONLY); + if (fd < 0) { + logg->logMessage("%s(%s:%i): open failed", __FUNCTION__, __FILE__, __LINE__); + return false; + } + + length = 0; + + for (;;) { + const size_t minCapacity = length + MIN_BUFFER_FREE + 1; + if (capacity < minCapacity) { + if (resize(minCapacity) != 0) { + logg->logMessage("%s(%s:%i): DynBuf::resize failed", __FUNCTION__, __FILE__, __LINE__); + goto fail; + } + } + + const ssize_t bytes = ::read(fd, buf + length, capacity - length - 1); + if (bytes < 0) { + logg->logMessage("%s(%s:%i): read failed", __FUNCTION__, __FILE__, __LINE__); + goto fail; + } else if (bytes == 0) { + break; + } + length += bytes; + } + + buf[length] = '\0'; + result = true; + + fail: + close(fd); + + return result; +} + +int DynBuf::readlink(const char *const path) { + ssize_t bytes = MIN_BUFFER_FREE; + + for (;;) { + if (static_cast<size_t>(bytes) >= capacity) { + const int err = resize(2 * bytes); + if (err != 0) { + return err; + } + } + bytes = ::readlink(path, buf, capacity); + if (bytes < 0) { + return -errno; + } else if (static_cast<size_t>(bytes) < capacity) { + break; + } + } + + length = bytes; + buf[bytes] = '\0'; + + return 0; +} + +bool DynBuf::printf(const char *format, ...) { + va_list ap; + + if (capacity <= 0) { + if (resize(2 * MIN_BUFFER_FREE) != 0) { + logg->logMessage("%s(%s:%i): DynBuf::resize failed", __FUNCTION__, __FILE__, __LINE__); + return false; + } + } + + va_start(ap, format); + int bytes = vsnprintf(buf, capacity, format, ap); + va_end(ap); + if (bytes < 0) { + logg->logMessage("%s(%s:%i): fsnprintf failed", __FUNCTION__, __FILE__, __LINE__); + return false; + } + + if (static_cast<size_t>(bytes) > capacity) { + if (resize(bytes + 1) != 0) { + logg->logMessage("%s(%s:%i): DynBuf::resize failed", __FUNCTION__, __FILE__, __LINE__); + return false; + } + + va_start(ap, format); + bytes = vsnprintf(buf, capacity, format, ap); + va_end(ap); + if (bytes < 0) { + logg->logMessage("%s(%s:%i): fsnprintf failed", __FUNCTION__, __FILE__, __LINE__); + return false; + } + } + + length = bytes; + + return true; +} |