Cosmetic improvements for options-handling code in ECPGconnect().

The comment describing the string format was a lie.  Make it agree with
reality, add/improve some other comments, fix coding style for loops with
empty bodies.  Also add an Assert that we counted parameters correctly,
because the spread-out logic for that looks pretty fragile.

No actual bugs fixed here, so no need to back-patch.

Discussion: https://postgr.es/m/848B1649C8A6274AA527C4472CA11EDD5FC70CBE@G01JPEXMBYT02

diff --git a/src/interfaces/ecpg/ecpglib/connect.c b/src/interfaces/ecpg/ecpglib/connect.c
index ec01f67b61d5e8f0b88f84346451d2135a78b777..4f361510c36575ec64078401942efd9bc034dcb3 100644 (file)
--- a/src/interfaces/ecpg/ecpglib/connect.c
+++ b/src/interfaces/ecpg/ecpglib/connect.c
@@ -516,9 +516,9 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
             options ? "with options " : "", options ? options : "",
             (user && strlen(user) > 0) ? "for user " : "", user ? user : "");
 
+   /* count options (this may produce an overestimate, it's ok) */
    if (options)
        for (i = 0; options[i]; i++)
-           /* count options */
            if (options[i] == '=')
                connect_params++;
 
@@ -585,8 +585,12 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
    {
        char       *str;
 
-       /* options look like this "option1 = value1 option2 = value2 ... */
-       /* we have to break up the string into single options */
+       /*
+        * The options string contains "keyword=value" pairs separated by
+        * '&'s.  We must break this up into keywords and values to pass to
+        * libpq (it's okay to scribble on the options string).  We ignore
+        * spaces just before each keyword or value.
+        */
        for (str = options; *str;)
        {
            int         e,
@@ -594,13 +598,21 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
            char       *token1,
                       *token2;
 
-           for (token1 = str; *token1 && *token1 == ' '; token1++);
-           for (e = 0; token1[e] && token1[e] != '='; e++);
+           /* Skip spaces before keyword */
+           for (token1 = str; *token1 == ' '; token1++)
+                /* skip */ ;
+           /* Find end of keyword */
+           for (e = 0; token1[e] && token1[e] != '='; e++)
+                /* skip */ ;
            if (token1[e])      /* found "=" */
            {
                token1[e] = '\0';
-               for (token2 = token1 + e + 1; *token2 && *token2 == ' '; token2++);
-               for (a = 0; token2[a] && token2[a] != '&'; a++);
+               /* Skip spaces before value */
+               for (token2 = token1 + e + 1; *token2 == ' '; token2++)
+                    /* skip */ ;
+               /* Find end of value */
+               for (a = 0; token2[a] && token2[a] != '&'; a++)
+                    /* skip */ ;
                if (token2[a])  /* found "&" => another option follows */
                {
                    token2[a] = '\0';
@@ -614,11 +626,14 @@ ECPGconnect(int lineno, int c, const char *name, const char *user, const char *p
                i++;
            }
            else
-               /* the parser should not be able to create this invalid option */
+           {
+               /* Bogus options syntax ... ignore trailing garbage */
                str = token1 + e;
+           }
        }
-
    }
+
+   Assert(i <= connect_params);
    conn_keywords[i] = NULL;    /* terminator */
 
    this->connection = PQconnectdbParams(conn_keywords, conn_values, 0);