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ELFTC_STRING_TABLE_CREATE(3) FreeBSD Library Functions Manual NAME elftc_string_table_create, elftc_string_table_destroy, elftc_string_table_from_section, elftc_string_table_image, elftc_string_table_insert, elftc_string_table_lookup, elftc_string_table_remove, elftc_string_table_to_string - convenience routines for handling ELF string tables SYNOPSIS #include <libelftc.h> Elftc_String_Table * elftc_string_table_create(size_t sizehint); void elftc_string_table_destroy(Elftc_String_Table *table); Elftc_String_Table * elftc_string_table_from_section(Elf_Scn *scn, size_t sizehint); const char * elftc_string_table_image(Elftc_String_Table *table, size_t *size); size_t elftc_string_table_insert(Elftc_String_Table *table, const char *string); size_t elftc_string_table_lookup(Elftc_String_Table *table, const char *string); int elftc_string_table_remove(Elftc_String_Table *table, const char *string); const char * elftc_string_table_to_string(Elftc_String_Table *table, size_t offset); DESCRIPTION This manual page documents convenience routines for handling ELF string tables. Function elftc_string_table_create() creates a new, empty string table. The argument sizehint provides a hint about the expected number of bytes of string data in the table. If the argument sizehint is zero, an implementation-defined default will be used instead. Function elftc_string_table_destroy() destroys the previously allocated string table specified by argument table, and frees the internal resources allocated for it. Function elftc_string_table_from_section() creates a new string table and initializes it based on the contents of the section specified by argument scn. This section must be of type SHT_STRTAB. The argument sizehint provides a hint about expected number of bytes of string data in the table. If the value of sizehint is zero, an implementation-default will be used instead. Function elftc_string_table_image() returns a pointer to the ELF representation of the contents of the string table specified by argument table. If argument size is not NULL, the size of the ELF representation Function elftc_string_table_insert() inserts the NUL-terminated string pointed to by argument string into the string table specified by argument table, and returns an offset value usable in ELF data structures. Multiple insertions of the same content will return the same offset. The offset returned will remain valid until the next call to elftc_string_table_image(). Function elftc_string_table_lookup() looks up the string referenced by argument string in the string table specified by argument table, and if found, returns the offset associated with the string. The returned offset will be valid until the next call to elftc_string_table_image(). Function elftc_string_table_remove() removes the string pointed by argument string from the string table referenced by argument table, if it is present in the string table. Function elftc_string_table_to_string() returns a pointer to the NUL- terminated string residing at argument offset in the string table specified by argument table. The value of argument offset should be one returned by a prior call to elftc_string_table_insert() or elftc_string_table_lookup(). The returned pointer will remain valid until the next call to elftc_string_table_insert() or elftc_string_table_image(). Memory Management The library "libelftc" library manages its own memory allocations. The application should not free the pointers returned by the string table functions. IMPLEMENTATION NOTES The current implementation is optimized for the case where strings are added to a string table, but rarely removed from it. The functions elftc_string_table_insert(), elftc_string_table_lookup(), elftc_string_table_remove() and elftc_string_table_to_string() have O(1) asymptotic behavior. The function elftc_string_table_image() can have O(size) asymptotic behavior, where size denotes the size of the string table. RETURN VALUES Functions elftc_string_table_create() and elftc_string_table_from_section() return a valid pointer to an opaque structure of type Elftc_String_Table on success, or NULL in case of an error. The function elftc_string_table_image() returns a pointer to an in-memory representation of an ELF string table on success, or NULL in case of an error. Functions elftc_string_table_insert() and elftc_string_table_lookup() return a non-zero offset on success, or zero in case of an error. Function elftc_string_table_remove() returns a positive value on success, or zero in case of an error. Function elftc_string_table_to_string() returns a valid pointer on success, or NULL in case of an error. SEE ALSO