diff options
Diffstat (limited to 'src/lib/util/cstrpool.c')
-rw-r--r-- | src/lib/util/cstrpool.c | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/src/lib/util/cstrpool.c b/src/lib/util/cstrpool.c new file mode 100644 index 00000000000..17b43b325a6 --- /dev/null +++ b/src/lib/util/cstrpool.c @@ -0,0 +1,100 @@ +/*************************************************************************** + + cstrpool.c + + Constant string pool helper class. + +***************************************************************************/ + +#include "cstrpool.h" + + +//************************************************************************** +// CONST STRING POOL +//************************************************************************** + +//------------------------------------------------- +// const_string_pool - constructor +//------------------------------------------------- + +const_string_pool::const_string_pool() +{ +} + + +//------------------------------------------------- +// add - add a string to the string pool +//------------------------------------------------- + +const char *const_string_pool::add(const char *string) +{ + // if NULL or a small number (for some hash strings), just return as-is + if (FPTR(string) < 0x100) + return string; + + // scan to find space + for (pool_chunk *chunk = m_chunklist.first(); chunk != NULL; chunk = chunk->next()) + { + const char *result = chunk->add(string); + if (result != NULL) + return result; + } + + // no space anywhere, create a new pool and prepend it (so it gets used first) + const char *result = m_chunklist.prepend(*global_alloc(pool_chunk)).add(string); + assert(result != NULL); + return result; +} + + +//------------------------------------------------- +// contains - determine if the given string +// pointer lives in the pool +//------------------------------------------------- + +bool const_string_pool::contains(const char *string) +{ + // if NULL or a small number (for some hash strings), then yes, effectively + if (FPTR(string) < 0x100) + return true; + + // scan to find it + for (pool_chunk *chunk = m_chunklist.first(); chunk != NULL; chunk = chunk->next()) + if (chunk->contains(string)) + return true; + + return false; +} + + +//------------------------------------------------- +// pool_chunk - constructor +//------------------------------------------------- + +const_string_pool::pool_chunk::pool_chunk() + : m_next(NULL), + m_used(0) +{ +} + + +//------------------------------------------------- +// add - add a string to this pool +//------------------------------------------------- + +const char *const_string_pool::pool_chunk::add(const char *string) +{ + // get the length of the string (no string can be longer than a full pool) + int bytes = strlen(string) + 1; + assert(bytes < POOL_SIZE); + + // if too big, return NULL + if (m_used + bytes > POOL_SIZE) + return NULL; + + // allocate, copy, and return the memory + char *dest = &m_buffer[m_used]; + m_used += bytes; + memcpy(dest, string, bytes); + return dest; +} |