6f0cef9353
The code associated with EXEC SQL DEFINE was unreadable and full of bugs, notably: * It'd attempt to free a non-malloced string if the ecpg program tries to redefine a macro that was defined on the command line. * Possible memory stomp if user writes "-D=foo". * Undef'ing or redefining a macro defined on the command line would change the state visible to the next file, when multiple files are specified on the command line. (While possibly that could have been an intentional choice, the code clearly intends to revert to the original macro state; it's just failing to consider this interaction.) * Missing "break" in defining a new macro meant that redefinition of an existing name would cause an extra entry to be added to the definition list. While not immediately harmful, a subsequent undef would result in the prior entry becoming visible again. * The interactions with input buffering are subtle and were entirely undocumented. It's not that surprising that we hadn't noticed these bugs, because there was no test coverage at all of either the -D command line switch or multiple input files. This patch adds such coverage (in a rather hacky way I guess). In addition to the code bugs, the user documentation was confused about whether the -D switch defines a C macro or an ecpg one, and it failed to mention that you can write "-Dsymbol=value". These problems are old, so back-patch to all supported branches. Discussion: https://postgr.es/m/998011.1713217712@sss.pgh.pa.us
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.