Re: Adding some const keywords to external interfaces

I have applied this. D'Arcy feels it is safe, and I think I agree now.

If anyone has a problem, let us know. He believes it completes
constification of the libpq API.

> I am sending this patch to hackers because I think it needs some
> discussion before being added. I'm not 100% sure that there
> isn't some internal issue with making these changes but so far
> it seems to work for me.
>
> In interfaces/libpq/libpq-fe.h there are some structures that include
> char pointers. Often one would expect the user to send const strings
> to the functions using these pointers. The following keeps external
> programs from failing when full error checking is enabled.
>
>
> *** ../src.original/./interfaces/libpq/libpq-fe.h Sat Jan 16 07:33:49 1999
> --- ./interfaces/libpq/libpq-fe.h Fri Jan 22 07:14:21 1999
> ***************
> *** 100,108 ****
> pqbool html3; /* output html tables */
> pqbool expanded; /* expand tables */
> pqbool pager; /* use pager for output if needed */
> ! char *fieldSep; /* field separator */
> ! char *tableOpt; /* insert to HTML <table ...> */
> ! char *caption; /* HTML <caption> */
> char **fieldName; /* null terminated array of repalcement
> * field names */
> } PQprintOpt;
> --- 100,108 ----
> pqbool html3; /* output html tables */
> pqbool expanded; /* expand tables */
> pqbool pager; /* use pager for output if needed */
> ! const char *fieldSep; /* field separator */
> ! const char *tableOpt; /* insert to HTML <table ...> */
> ! const char *caption; /* HTML <caption> */
> char **fieldName; /* null terminated array of repalcement
> * field names */
> } PQprintOpt;
> ***************
> *** 113,124 ****
> */
> typedef struct _PQconninfoOption
> {
> ! char *keyword; /* The keyword of the option */
> ! char *envvar; /* Fallback environment variable name */
> ! char *compiled; /* Fallback compiled in default value */
> ! char *val; /* Options value */
> ! char *label; /* Label for field in connect dialog */
> ! char *dispchar; /* Character to display for this field */
> /* in a connect dialog. Values are: */
> /* "" Display entered value as is */
> /* "*" Password field - hide value */
> --- 113,124 ----
> */
> typedef struct _PQconninfoOption
> {
> ! const char *keyword; /* The keyword of the option */
> ! const char *envvar; /* Fallback environment variable name */
> ! const char *compiled; /* Fallback compiled in default value */
> ! char *val; /* Options value */
> ! const char *label; /* Label for field in connect dialog */
> ! const char *dispchar; /* Character to display for this field */
> /* in a connect dialog. Values are: */
> /* "" Display entered value as is */
> /* "*" Password field - hide value */
> *** ../src.original/./interfaces/libpq/fe-print.c Fri Jan 22 07:02:10 1999
> --- ./interfaces/libpq/fe-print.c Fri Jan 22 07:03:09 1999
> ***************
> *** 681,687 ****
> p = border;
> if (po->standard)
> {
> ! char *fs = po->fieldSep;
>
> while (*fs++)
> *p++ = '+';
> --- 681,687 ----
> p = border;
> if (po->standard)
> {
> ! const char *fs = po->fieldSep;
>
> while (*fs++)
> *p++ = '+';
> ***************
> *** 693,699 ****
> for (len = fieldMax[j] + (po->standard ? 2 : 0); len--; *p++ = '-');
> if (po->standard || (j + 1) < nFields)
> {
> ! char *fs = po->fieldSep;
>
> while (*fs++)
> *p++ = '+';
> --- 693,699 ----
> for (len = fieldMax[j] + (po->standard ? 2 : 0); len--; *p++ = '-');
> if (po->standard || (j + 1) < nFields)
> {
> ! const char *fs = po->fieldSep;
>
> while (*fs++)
> *p++ = '+';
> *** ../src.original/./interfaces/libpq/fe-connect.c Fri Jan 22 07:04:03 1999
> --- ./interfaces/libpq/fe-connect.c Fri Jan 22 07:13:09 1999
> ***************
> *** 48,54 ****
> static void freePGconn(PGconn *conn);
> static void closePGconn(PGconn *conn);
> static int conninfo_parse(const char *conninfo, char *errorMessage);
> ! static char *conninfo_getval(char *keyword);
> static void conninfo_free(void);
> static void defaultNoticeProcessor(void *arg, const char *message);
>
> --- 48,54 ----
> static void freePGconn(PGconn *conn);
> static void closePGconn(PGconn *conn);
> static int conninfo_parse(const char *conninfo, char *errorMessage);
> ! static const char *conninfo_getval(const char *keyword);
> static void conninfo_free(void);
> static void defaultNoticeProcessor(void *arg, const char *message);
>
> ***************
> *** 172,179 ****
> PGconn *
> PQconnectdb(const char *conninfo)
> {
> ! PGconn *conn;
> ! char *tmp;
>
> /* ----------
> * Allocate memory for the conn structure
> --- 172,179 ----
> PGconn *
> PQconnectdb(const char *conninfo)
> {
> ! PGconn *conn;
> ! const char *tmp;
>
> /* ----------
> * Allocate memory for the conn structure
> ***************
> *** 284,291 ****
> PGconn *
> PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions, const char *pgtty, const char *dbName, const char *login, const char *pwd)
> {
> ! PGconn *conn;
> ! char *tmp;
>
> /* An error message from some service we call. */
> bool error = FALSE;
> --- 284,291 ----
> PGconn *
> PQsetdbLogin(const char *pghost, const char *pgport, const char *pgoptions, const char *pgtty, const char *dbName, const char *login, const char *pwd)
> {
> ! PGconn *conn;
> ! const char *tmp;
>
> /* An error message from some service we call. */
> bool error = FALSE;
> ***************
> *** 1137,1143 ****
> char *pname;
> char *pval;
> char *buf;
> ! char *tmp;
> char *cp;
> char *cp2;
> PQconninfoOption *option;
> --- 1137,1143 ----
> char *pname;
> char *pval;
> char *buf;
> ! const char *tmp;
> char *cp;
> char *cp2;
> PQconninfoOption *option;
> ***************
> *** 1343,1350 ****
> }
>
>
> ! static char *
> ! conninfo_getval(char *keyword)
> {
> PQconninfoOption *option;
>
> --- 1343,1350 ----
> }
>
>
> ! static const char *
> ! conninfo_getval(const char *keyword)
> {
> PQconninfoOption *option;
>
>
> --
> D'Arcy J.M. Cain <darcy(at){druid|vex}.net> | Democracy is three wolves
> http://www.druid.net/darcy/ | and a sheep voting on
> +1 416 424 2871 (DoD#0082) (eNTP) | what's for dinner.
>
>

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